Australia

Without commenting any of your other points, saying that "our stuff is made by corporations so it's the individuals fault for buying it" is in my opinion extremely shortsighted.
You don't have any influence on the supply chain. Even with exceptions like Fairphone, harmful ways to produce are mostly cheaper than less harmful ways. On one end, those who produce cheaper have the competitive advantage, on the other you have low, non-increasing wages.
This also applies to the "buy quality" thing. Even if the word "quality" had an objective definition, it's incredibly hard to decide that. Expensive items could be made out if cheap materials, which feel valuable but aren't. The hardware could be good, but software updates are only supplied in the short-term.
And after all, people have work in the morning and I don't think it's reasonable to expect them to sacrifice what little free time they have into researching all of their consumption. It's a systematic issue, and these tips floating around feel like bikeshedding. Yes they're nice, good on you for doing it, but does it really fix any of the pressing issues?
it's late so please apologize if this text doesn't make any sense.