Apple Mail not filtering messages after Tahoe upgrade

After upgrading to Tahoe 26.0 today, my Apple Mail has stopped filtering messages to mailboxes I have created. I checked the "rules" tab and all my rules are still in place, but all my mail is just going to my inbox.

I suspect this has something to do with the fact that I have a gmail address and there is some sort of conflict with my Google account, but since I never had this problem previously (before the upgrade), I don't even know where to start troubleshooting this.