However you might like to note the time it happens next and then on your next reboot take a quick look in your journal and perhaps point something like lnav at /var/log and see if anything jumps out.
journalctl --since "2023-04-13 09:00:00" --until "2023-04-13 09:05:00"
https://docs.lnav.org/en/v0.11.1/usage.html#time
A lot of Linux software isn't very intrinsically robust and the result is lots of janky stuff that isn't caught by tests, and only affects a small number of people in difficult to reproduce ways.
Yet you will almost certainly have something Linux running in your home somewhere. Obviously, I am making quite an assumption here with regards what OSs run in your home, but Linux powers way more stuff than any other OS on the planet by a massive margin.
Your casual dismissal of Linux misses several points. Linux is just a kernel - 'tis what boots and stuff. Statically typed bollockary doesn't even feature at this level, yet we have some wondrous stuff on display. We get eBPF to play with for fiddling quite unceremoniously with network packets and much, much, more. We have way more file systems than you can count ... OK put your socks back on. We have multiple schedulers and way more firewalling systems than is reasonable. nft looks like it might be quite useful. It's the fourth one I've dealt with (ipfw, ipchains, iptables) so it should work out.
That's the kernel alone - 1000s of devs working on it - way more than any other OS kernel.
There are multiple stable WMs, GUIs and whatever. I've stuck with KDE since a shaky self compile of 2.0 a fair few years ago.
Linux runs quite a bit of your life somewhere even if it's only your telly.
That's quite an esoteric issue that I have never seen on a lot of disparate hardware, all with KDE, since early v2. I'd log an issue, you never know it might get fixed and you can get on with life.