I basically give companies 0 strikes anymore, and assume the "unsubscribe" link is at best, a dark pattern that only unsubscribes me from that 1 out of their 100 "channels," and at worst, confirms my E-mail address. "Report Spam" immediately.
I assume the unsubscribe link is malicious - if I didn't ask to be subscribed, why would I trust an unsubscribe link? Spam baby spam.
I unsubscribe twice (allowing for one possible bug), then spam.
And, as others have noted, unsubscribe cannot involving going and logging into their system. If I need to do that, it generally goes directly to spam.
If I didn't intentionally request non-transactional mail, it is spam. By definition.
Mark it as such.