Depends on the use case.
I use Nobara on my gaming rig because I wanted up-to-date packages without being on the cutting edge like Arch. And I also wanted all the lower level gaming optimizations without having to set it all up manually. Plus, KDE is soooooo nice.
Debian on my servers because I want extreme stability with a community-driven distro.
Linux Mint on my personal laptops, because I like having the good things from Ubuntu without all the junk. Plus the Cinnamon desktop environment has been rock stable for me. It’s my goto workhorse distro. If I don’t need something with a specialized or specific use case, I throw Mint on.
Arch on my old junker devices that I don’t use much because I like making them run super fast and look sexy and testing out different WM’s and DE’s.
Void on my junkers that I actually want to use frequently because it’s super performant and light on resources without needing to be built manually like Arch.
Ubuntu server if I am feeling stanky and lazy and just need something quick for a testing VM or container host in my home lab.
I’ve been using KDE for over 4 years on over a dozen different machines and 5+ distros and I’ve never had major problems with crashing.
I do experience small bugs fairly often. Maybe once every month or two, little glitches or odd window behavior. Nothing huge, but they do happen. To be fair, I like to modify and customize KDE quite a bit, so that is probably causing some of my issues.
In my experience, Cinnamon is the most stable DE I’ve used by far. Least amount of random bugs, simple but stable. I don’t think I’ve ever had Cinnamon crash on me actually.