> OP put their e-mail in cleartext, unobfuscated, in their profile. The blame is on part of the spammers. Countermeasures should be done by OP (and their e-mail host), not by GH.

According Github's site policies [0], they've explicitly outlawed this type of behavior meaning it's their responsibility to police and enforce this by punishing users on their platform who they find to be engaging in it:

"You may not use information from the Service (whether scraped, collected through our API, or obtained otherwise) for spamming purposes, including for the purposes of sending unsolicited emails to users"

[0] https://docs.github.com/en/site-policy/acceptable-use-polici...