You'd have a comparable number of bug fixes for any such big DE. It's just that KDE communicates on this. And if you look closer, the stuff being listed is often niche, not blocking or affects relatively new features. There are not a lot of regressions. I blindly update KDE these days, and use a rolling release distro to benefit from the improvements quickly.

At that size of a project everything will have bugs. With the current way we develop software it's unavoidable. If they're not stopping you from doing what you want to, then "everything works" is true.

everything works for my workflow*.

That said I don't use a lot of kde specific apps, rather opt for best-in-class, and terminal for others. Still - the system itself is stable.