Maybe because it's combo of reasons?

1. Marketers want implement features fast
2. Bad QA testing or missing at all
3. Modern desktop development suck a lot because of tools was created for that like electron
4. Quality of modern junior/middle developers comparing to old developers suck too ,modern uni not teaching anything useful in reality. Also people coming here to make money only mostly old developers was real true geeks

Also hardware continues to improve at a rate fast enough that we can just let it chug through software issues for a long time without significant perceived issues.

This is exactly what I was going to say. People only make things to the constraints they're given. If you reduce the constraints they're not going to make anything any better. There's no reason for a modern calculator designer to write stuff in assembly if they don't have to.