The world I live in (America) seems to be packed with people who expect me to buy things from them, but to whom it never seems to occur, that I as a customer might need to know something BASIC about the product or service.

Right now, for example, I want to buy curtains for my living room.

Now. It seems straightforward enough to me, that if someone makes curtains to sell, that they would expect customers to be able to choose some that would actually FIT THE WINDOWS.

However, I have as yet, been unable to locate even ONE vendor who posts both the height AND THE WIDTH of the curtains they sell. Every single one, restrict their descriptions to a single parameter, and many don't even say whether they are telling me the height or the width.

The world seems to be full of such nonsense these days. It took me decades to find a dentist who would BOTH perform a root canal, AND FILL THE HOLE THEY DRILLED AFTERWARD.

I have never found or even heard of a doctor who performs skin biopsies, who is willing to provide me the results of the test I pay for, unless they find cancer. Apparently, all American doctors are required to sign a secret agreement that at no time, are they to inform a patient that they are okay. We all have to hope and pray to the gods above, that the doctor we use, has every detail of our contact information correct, AND that nothing ever goes wrong with their record keeping systems (unlike EVERYONE ELSE on the planet), the mail, or any of their computers or printers.

What other (non-political) examples of concerted, apparently intentional, incompetence or idiocy do we all have to put up with?

I think all this are just sign of endtime. Fakes and evil everywhere

Real Estate agents.
I want them to know more than I do about real estate.

'Are there any geological reports on the site?'
'Huh?'

'Is it in a flood zone?'
'Looks dry enough.'

I want to tear my hair out around them.

lets not even consider used car, boat or recreational vehicle salesmen.
I'm a mechanic. It never fails that no matter what mechanical device I am trying to buy, the seller tries to convince me of some quality I know it can't possess or that something I know it needs is not required. They will even argue their point as if arguing changes the physics.

The salesman I bought my truck from years ago told me it was $3100.00. I took out 31 hundred dollar bills and started to point things out on the truck. Everytime I proved his lie was false or found something that wasn't right, I put away $100.
I ended up paying $1900 for the truck and, I had him throw in a power steering hose and the state inspection.

He could have walked away anytime but the sight of that wad of cash locked him to me like a leech. The fact that he agreed on $1900 tells me he knew it wasn't worth $3100.

I've had the 4x4 truck for 6 years, still runs.

Not to minimize your OP concerns but while I was making dinner I realized I have something that was low dollar (and not on sale) but very high quality. A key chain knife sharpener.

Okay back on OP.
I get my meds thru the mail from the VA.
Most of the time the Rx instructions are on the bottle.
Well, this new med he sent me for my appetite is in a bottle and needs to be kept in the fridge.
So I open and toss the box and stick it in the fridge.
The next day (trash went to the curb) I figure I'll give it a try.
I get the bottle out and I look at the label and its the generic label, No dosage or instructions.
So I figure I'll just go online and go to the VA site and look up my records. There are no doseage instructions for any of my meds. So I shoot the doc an email (I don't have a phone) and wait. 3 days later and I still got no reply. I bet if I stopped sending my payment I would get a reply.
Is it that difficult to open the box and put the sticker on the actual bottle?
Is it that difficult to add a field to my RX list that has the instructions?
What is the point of having Secure Messaging with your doctor if they don't answer?

Many people shop online and get along fine with that! They save on products and save, free postage. I prefer to bye houshold things at my local stores.
So far , I do fine with finding most things in sizes, colors, etc.

Many people do have problems with doctors. Insurances may play a huge part in where a person goes for Care. Offices make mistakes sometimes in billing for certain care too.

I m blessed I check everything out and it comes out ok.
At this point I like my doctors.

Concerted and intentional incompetence or idiocy?
Less from companies or service providers and more from consumers, and a lot due to consumer expectations.

I find a lot of over/underspecialization.
Like a company or service overspecializes into its niche to such a degree it develops its own language and shortcuts to speed up production.
At the same time, as a consumer, not having to worry about it at all, how it works, what it means, only that it does work, fulfills a need, so completely underspecializing in that knowledge and relying on the company to have my best interest at heart, or demanding they fill in where I am too lazy, leading to a lot of miscommunication and unrealistic expectations.
Like the I.T. department. Or Starbucks asking me if I want a half frap 2 pump moch vente chino midgrind or something.
I have no idea what that means. I don't want to follow computer or coffee aficionado quarterly to figure out what it means.

I do remember working in video departments/stores and people would come in and ask questions like "do you have that one movie that just came out recently? Agh...it had that one guy? Ummm...what's his name? Also had that girl that was on t.v. not too long ago. Conan I think? Did you see that? Just came out in theaters like a year? Maybe 2 ago? You know what I'm talking about? Might be in comedy, maybe drama? Do you have that movie yet?"

I also find companies that keep trying to outsource training/free work onto the customer.
Like McDonalds and their self service kiosks, or Krogers/walmart with their self checkout.
I even remember reading here in the forums someone wanting schools to focus more on skills that make graduates more competitive in the job market. Which is just putting the cost of training onto taxpayers instead of businesses training people to do the jobs the businesses want.
Companies want to keep employee costs down (imo in large part due to taxes and inflation creating the need for constant growth, but that is getting into the political), unfortunately that is influencing what is spent to actually train the employees adequately.

I remember moving to a new state and trying to get a job as a real estate appraiser (before appraisal management companies were created). Companies wouldn't even talk to me unless I brought in at least 3 mortgage originators/underwriters that would provide them business.
Yet many of them would hire a random nephew or kid or brother with no experience or contacts whatsoever. Thanks to the requirements for becoming a licensed appraiser, licensed appraisers are being asked to basically do less business and train their future competition.

From my perspective there isn't a lot of "concerted and intentional incompetence or idiocy" on the part of companies or service providers.
IMO/IME the perception stems a lot from (possibly a different thread but ultimately government intervention and/or) consumer incompetence/laziness/unrealistic expectations.
People not doing what they should be doing in their research and preparation and/or needing constant safety nets for when they make a mistake because they don't know what they're doing because they've stopped thinking before hand since so many companies have put so much effort into making it so consumers don't have to creating the specialization imbalance.