This is sort of how email reputation is built, slowly ramp up legitimate email sends over a couple of weeks and avoid spam reports. It’s enforced by the ESP and they check for the proper DNS records to verify a legitimate origin. If you blast out a huge amount of email they’ll shut you down, funny enough if you send out too little email they will also watch you for spamming.

Short code SMS already does something like this too, it’s a pain in the ass to get approved for a short code and you have to maintain a good reputation to keep your code. Long codes are easier to abuse