I urge everyone to stop clicking unsubscribe, ever, unless you explicitly subscribed to something. [edit: Even that automatically enabled “subscribe to our mailing list” nonsense, or “click this to not subscribe”, or whatever stupid games they play on us these days. No. Don’t let them joke you around.]
Not saying you didn’t, just wanted to take this opportunity for a cheeky PSA :)
Ironically, conditioning people to respect the unsubscribe button has, probably, insidiously led to more spam making it into people’s inboxes than anything else in recent memory.
[edit: to answer the Why not both? ] Because incentives makes our world go around. Make no mistake: They don’t give a damn about you or your inbox and will do anything for those sweet sweet engagement and conversion metrics. Unsubscribe makes them feel the pain (this is the jncentive), and it helps them not take your inbox for granted.
Making them eat bad spam rep score is the only weapon we have, to make them treat our inbox with respect. Use it.