Some of it is the fault of AI and the belief that software is super easy to create now and maintenance won't be an issue in the future, mainly by folks who have very little to no experience with writing software but attempt it via the many ways you can do it with AI these days.

Then there's the shiny object syndrome of humanity in general even if we just look at websites they went through so many different cycles, plain html, flash, everything built with bootstrap.css, then came the frameworks, then back to SSR/SSG, etc... etc..

Both of those are just symptoms of a larger disease , namely lack of enthusiasm in general has fallen, a lot of it has to do with how demanding day to day software jobs have gotten, or how financially unstable the younger generations feel so they rarely set aside any time for creative endeavors and passion projects