Absolutely this. UIs have been "good enough" for a very long time now. There were some minor breakthroughs/inventions along the way, but half of them were probably just responses to shifting usage patterns. You build up muscle memory and you're set.

One example that comes to mind is more powerful/prominent search features. In the 90s, as a home user, you had a folder with some documents and in total, the number of installed games plus apps was probably around a dozen. So it was ok that on Windows, searching for files was hidden in a sub-menu and rather slow. Today, you have a bazillion tools and apps, games, documents from 30 years of migrating to a new system, backups, so you make search faster to access.

People value consistency and gradual development, not failed, half-baked overhauls like the Windows 8 debacle. And obviously that stuff actually works. Which is continuing to be a big downside of KDE or Linux in general. Too many components working together, maintained by different teams and ever-changing. It's basically up to the Distros to find the perfect combination of library and software versions to get a good experience.