I think that's fine. If 20% of the emails from some company (let's say Paypal) are spam, then all email providers (especially Gmail, the largest provider) should mark ALL of their emails as spam by default until they stop spending spam. If they want to keep spamming, they can at least humiliate themselves by telling people to check their spam folders for their emails.
Dangerous, since this invites genuine service emails to be junked.
I think that's fine. If 20% of the emails from some company (let's say Paypal) are spam, then all email providers (especially Gmail, the largest provider) should mark ALL of their emails as spam by default until they stop spending spam. If they want to keep spamming, they can at least humiliate themselves by telling people to check their spam folders for their emails.