It cannot do PGP, by design, just for a very obvious fault. It won't let you use your own domain and web storage. Sorry, no contest.

I use Gmail with my own domain (you have to pay for the privilege but Google Workspace has been very reliable and flexible for my purposes)

I'd rather use Google's web storage than my own. I don't have the time nor the expertise to implement multi-region replication etc.

I understand that granting Google access to one's emails might be a dealbreaker for journalists, dissidents etc, though - so clearly Gmail is no good if you have legitimate need for PGP.