Alright, I have #AntiX Linux installed on partition #2, with full screen resolution and working audio. Quite nice. Would have been nicer if it didn't fuck up my boot partition by not recognizing NetBSD, so some tinkering will be necessary to be able to boot that again. You'd think this wouldn't be a problem anymore, it was probably a decade ago that I was making contributions to os-prober - actually, apparently you look that up and my fork is the first thing that comes up anymore, so I bet it's deprecated in Debian upstream, and that was 12 years ago. I should archive that repo so people don't try to use it, as that's probably dangerously out of date now lol
Anyway. Getting back into NetBSD is, ironically, probably my immediate next thing to care about.