How are so many things now worse quality and higher priced than their own knock-offs?

They earned public trust and brand-recognition over many years. Then, once they became the de facto product, they started min-maxing their production. Smaller portions, cheaper ingredients, automating as much of the production line as possible to cut employees, reducing wages for "less work", etc. They're hoping no one would notice that the product you're buying isn't living up to the original standard.

If you're willing to pay the same price for cheaper production, then the company can literally make money without having to sell more product. They can show in their shareholder meetings that sales are going way up, even though consumer purchases may not have changed much at all. Heck, even if sales are going down, profits could still show an increase!

Then of course, there's "inflation," which they use to justify raising prices over time. Even though the product is worse than the original, you're now paying way more for it.

This is the endgame of capitalism. Maximize profits at the cost of consumers. When money is the primary focus of a business, quality of goods and services will always degrade over time.

committing Sudoku in shame

The Pillsbury Doughboy has a bit of a belly, it might be difficult to disembowel himself with a math puzzle.

I am convinced the terms "generic" and "off brand" are both psyops to get people more into big brands.

Seppuku*

appeared as cheaper lower quality versions

They really never were. This was a reputation, yes, but it was not warranted. It's taken a hell of a long time for enough people to realize this.

Nothing significant has changed in the last couple of decades, at least. Maybe back into the 60s, 70s, 80s or so, I won't debate. But since the turn fo the century at a minimum, store brands almost always use a producer that produces for name brands. It's often literally the same product. At worst, it might be stuff that didn't quite make the name brand standards, or it might hvae a little less quality or something, but almost all of the time, it's the same thing.

There might be some exception - I certainly haven't tried the myriad of store brands for stores I haven't gone to, but i've been buying mostly store brands for quite a number of years now, and almost all the time, there's no difference.

Like one I can think of: Store-brand "Doritos" might have a bit less "cheese" on them. Or might have the same, depends. Most of the time it's the same thing, though.