G Suite domain hosting includes the email address and the user licenses (albeit free ones.) If you stop paying for G Suite (Google Workspace) the user licenses will be revoked. They will not be able to login to Google services, access Play Store / Music / Movies purchases, etc.
"What happens to my additional Google services and paid content if I don’t want to pay for Google Workspace premium features?
If you don’t upgrade to a Google Workspace subscription, you will not lose access to other Google Services, including YouTube, Google Photos, and Google Play, nor paid content, including YouTube and Play Store purchases."
https://support.google.com/a/answer/60217?hl=en#zippy=%2Cwha...
Also, they could have told their stuff who've been fielding questions online about this change online; it might have stopped a few of them from telling people they'd be losing all their Photos, paid-for content etc.
https://9to5google.com/2022/01/26/g-suite-legacy-free-person...
As you'd expect from Google it's vague and unfinished - what happens to the other users you don't choose to save, or perhaps you have to delete all but 10 users, and what happens to those 10 users anyway.
Tune in again in a few days and see what else has changed on that FAQ, or search for news articles about this process because they sure as hell aren't going to email you about it.
They can't even kill services properly any more!
"If you don’t upgrade to a Google Workspace subscription, you will not lose access to other Google Services, including YouTube, Google Photos, and Google Play, nor paid content, including YouTube and Play Store purchases."
Source: https://support.google.com/a/answer/60217?hl=en#zippy=%2Cwha...