Good software needs a really easy way to report bugs and get back to work. And people to triage the reports. I do not work for KDE, but the bug reporting process treats me like I do.
This has been my experience since KDE 4 too pretty much 4 out of 5 attempts i made to check out KDE, including trying KDE Neon (which included weird visual glitches that i never saw before in any desktop environment).
Though FWIW my latest attempt is openSUSE Tumbleweed running on my GPD Win 1 (which isn't exactly a mainstream device, though it does have an Intel integrated GPU which has open source drivers, which helps a bit) and it seems to work fine there. I do very light use of it however, mainly launching games and such - normally i'd be using Window Maker, but GPD Win 1 needed a very recent kernel to boot and also RandR to be configured to rotate the screen (the 'native' screen is actually in portrait mode but the computer uses it in landscape) and i didn't want to bother with that at the moment i installed it so i grabbed the first non-Gnome-based rolling distribution that had official support for some form of desktop environment that i expected to have a GUI application to setup rotation... which basically meant KDE :-P.
What distro? New or installed on top of something else?
I have run KDE Neon since a few years ago om two (admittedly high end) laptops and it has been very smooth.
I have been using always-latest KDE5 with Manjaro on a very old (Core 2 Duo, Intel graphics) laptop for some years already and it's perfect. Less than 5 crashes a year.
KDE4 would crash as soon as I attached an extra display. KDE5 also crashed often when it was immature. Now it works like a breeze. As somebody who has watched (and tried regularly) KDE since the inception of KDE3, I can say KDE has finally reached maturity (if not perfection) about 1.5 years ago.
It's working as it always has been for me, since the early days of 4. It's pretty much dead for me now.
For the record, this has been happening on many machines, and I don't use nvigia GPUs and similar stuff.
Also, I try to report bugs in software that I use, but KDE has the appearance of software which receives no QA at all. It's one thing to report a bug in sway or some XFCE application which crashes maybe once in a few years, and other to use something which crashes a dozen times a day. I'd be filling bugs all day long.