I just got a used Pixel 6a, and tried to install GOS on it using the web installer. I didn't get any errors or the like during the install, everything seemed fine, but now it boot loops. I tried flashing it again a few times, tried flashing from an Android 13 tablet instead of a Windows PC, nothing helped. Eventually I flashed Android 16 onto it with the Android Flash Tool, and it still boot loops.
I can't even use Recovery mode or Rescue mode, those boot loop, too.
Previously it had Android 14 on it, that seemed to work fine, but I haven't tried flashing that back on because whilst trying to figure this issue out, I ran into something about anti-rollback which I don't quite understand but which gives me the vibe that if I do that, I'll perma-brick this thing.
How do I get this thing working again? Ideally with GOS, but if I can at least get Android working on it, that'd be something.
I'll add that whilst I consider myself reasonably computer-savvy, I've never done anything more complicated on a smartphone than installing an app not on google play. This is my first time ever trying to install an OS on a phone.