The funny thing is that given how crap things have gotten it doesn't seem like it would be very hard at all to architect a, "radically improved" version of modern computer interfaces. We even have LLMs to help facilitate parts of the system that might have been historically difficult to implement. Why not instead of building a, "modern" Windows or Mac OS you made a, "useable" version which was optimized to run on anything or could run with any stalling on a modern computer? I don't want Windows 11; I want Windows 25' I want it to work orders of magnitude faster than Windows 98 rather than using Moore's Law to create something that can, "do more with more resources but averages out to roughly the same experience as previous generations."
We're still effectively using the same computers we were using when I was a kid in the 1990s.