Overall, a pretty good impression from KDE Linux #kdelinux . Everything I tried works smoothly. The only hiccup, the user is not a member of audio group by default, so it needed tweaking to make Milkytracker work. Now my kid is testing Roblox and it’s quite smooth, as much as the old laptop allows it.
Last time I checked, PipeWire expected audio device permissions to be granted dynamically, and would have trouble in multi-user environments if the users were in the audio group. (I don’t know your distro, but it’s possible this is why your user wasn’t in the audio group by default.) So if you run PipeWire, you might want to take a closer look at the issue.