I also really support you to stop but if promotional emails keep coming then changing your email is the best choice you can make
I'm sure there's a setting in our Email provider for blocking or ignoring emails from a specific email address.
As far as I know, since Stake only uses 1 email address dedicated for their promotions, OP can consider doing the address blocking or something related to that.
Give it a try, OP if there's a problem dealing with Stake's unsubscription list.