Downside of using Google apps on GrapheneOS?

[FlipSid]

No Google Messages is not a privacy respecting app.
For people on GrapheneOS who have worries, just don’t allow Network Connections.
In my case I want the RCS messaging because:

Simple Mobile Tools to be bought by ZipoApps

Google Messages, the reason is that if another person has it, the messages will be upgraded to RCS and E2EE. It is now the default on Samsung devices. The spam filter works pretty well at killing random spam messages too. No other open source messenger has any kind of E2EE and most of them are unmaintained eg qksms (Feb 2021), silence (Sep 2019) etc. SMSes can be backed up easily on device with sms-ie, which also supports MMS message components unlike QKSMS or Silence.

But other people other priorities
The apps from Google are all not privacy respecting, that’s one part.
The other part is sandboxed google play Services.
These are 2 different things from my understanding.