Spam Filtering is terrible, I'm seeing literally a 50% false positive rate.
It seems there is no way to Disable it completely.
The wiki says
Apparently, you can prevent the messages from being moved but you can't actually disable the filtering fully?????
See https://help.dreamhost.com/hc/en-us/articles/215686647-Technical-details-on-how-Anti-spam-filters-work which says