Buying the cheapest part that will last longer than the warranty period is the standard practice at most companies. It's not malicious, it's just what happens when life of a product isn't something that consumers want or are able to judge.
Sort of a chicken and egg problem I guess. What came first, the short lived product, or the consumer's desire to buy something newer and shinier.
People definitely want to buy new shiny things, but I fully disagree that product cycles and lifespans are the result of that desire. Companies have positioned themselves to scale uncontrollably at that cost of product lifespans. They make more money if people buy a new thing every 18 months, so they make the thing fail every 18 months instead of making something that has a longer term life. This practice can only be characterized as wasteful and greedy.
Spending less on components that are guaranteed to fail _is_ a malicious act. Apparently we're so far down the rabbit hole now that there are actually people who think that planned obsolescence is a feature. You're blowing my mind here in the worst possible way.
You say that spending less on parts you know will fail is malicious, but everything fails eventually. If you know that your resistors are likely to last 100 years, and your capacitors (even the best ones) are like to last 20 years, is it malicious to not spring for the resistors that will last 200 years? You have to make practical decisions about the level of quality that you're aiming for at some point.
I know that planned obsolescence is a thing, and it should be illegal (in certain forms). How common is it? I don't know. Do you? Maybe I should have said "it's not necessarily malicious", because it's not. You can make a cheap product just because you think there's a market for a cheaper version of a good product. Does that mean you want the thing you're making to fail? Not necessarily. Maybe you just want to serve a market that wants a cheaper version of something. I sometimes find myself wanting to buy the cheapest version of something because I only need it for a brief period of time. Is this wasteful? Sometimes. Should it be illegal for a company to sell me a cheap version of a thing? Maybe for environmental reasons, but not for consumer protection reasons.