I've read some stuff on this subject that hasn't given me a super definitive answer.
The docs say you have to be signed in to install apps, but doesn't mention if you have to be signed in for updates:
Signing in into a Google account is optional, unless you want to use features depending on being signed into an account. For example, some apps use Google account authentication instead of their accounts having a username and password. The Play Store requires being signed into an account in order to install apps or use in-app purchases.
This reply says you have to be logged in to get auto updates. I found a few other posts about Play Store updates not working but it's not clear whether they were logged in while having this problem.
I'm asking because Play Store shows no updates are available unless I log into a Google account, which I wasn't expecting. I've been using GOS since 2022 I think but only found out recently that using Aurora Store isn't recommended by GOS people. Now I've switched from a Pixel 6a to a 9a and this time I wanna do things right, so I got all my apps from either Play Store or F-Droid.
I don't want to be logged into Google 24/7 if I can help it though, even though the account I used to get the apps has fake info. I've moved away from Google as much as I can (without switching to Apple products obviously, ew) but as far as I'm concerned, osmand+ and libretube just don't cut it as maps and youtube replacements. So if I'm logged in all the time, even if it's an account with a fake name on it, it still means Google is learning crap about where I go and what I'm interested in.
So do I have to be logged in all the time to get auto updates? Or maybe I log in once a week or so to log in, do updates and log out? That would suck but tbh Aurora Store auto updates never worked for me so I'm actually already used to that...