Problem is many Android apps require Google Services and none of these will have it. So things like banking apps, parking payment apps, RCS text messaging apps, and even dating apps these days are going to refuse to run. Grapheneos has the advantage of the Google services sandboxed to reduce the impact of having it if you understand the implications, as well as features keeping other apps from talking to each other like how Facebook was caught using their apps to identify you to your web browser to allow every site you visit to identify you that has Meta provided services, even in incognito mode or when you opt out of or block their or third-party cookies.