I mean, that's the reality of using an Android phone. 95% of apps are built to use play services in some way, and while most of that can be ignored, apps using push notifs are almost always going to be play instead of unified push. Make the choice of either living with no push notifs, or having push notifs.

You can use GrapheneOS without push notifs, it's just inconvenient, and the average person wants convenience. This isn't a Graphene problem, it's a big tech influencing Android problem. The original comment makes it seem like Graphene is the issue, but other ROMs are going to encounter that same issue anyway (as I said, Android problem). So therefore I didn't lie, asshole.

Maybe you can use microG to get around notif issues, but that does require logging in. Use a Linux phone at that rate if you're not gonna use push notifs and don't need Android.