Interacted with the company, as in filed a support request, bought something from them, etc.

They already have my e-mail address, likely even verified. They're also somewhat normal companies, i.e. they have an address where the local DPA can send a friendly reminder, and while they will happily pass your (likely hashed) e-mail address to Facebook for ad targeting, actual selling to spammers is incredibly rare.

I often can't just filter the domain because I might actually need to deal with the company again (if I boycotted everyone who acts like a dick I'd be living in a cave).

Also, for many, unsubscribe actually works.