[jjav]

Based on my experience running mail servers for a long time and today, I'd say OP is right.

gmail spam filtering is terrible. On my various gmail accounts, I both get spam and the good email goes to the spam folder. And there's nothing you can do, you can mark it not-spam a thousand times and it's still a crapshoot.

I don't have any of those problems with my self-hosted email.