Many users aren't getting e-mails; it includes a lot of new users that in turn make bad edits without any possibility of knowing how to do them better, while other editors waste time talking to a wall. The consequence is pretty simple : edit quality becomes worse and other editors have less time to improve the database, making it steadily worse.

I estimate at least 30 active users concerned.

For proof, I provide a few exemples of users that are doing good edits, i.e. that would not willfully ignore the e-mails:
https://musicbrainz.org/edit/31761587
https://musicbrainz.org/edit/31725549
https://musicbrainz.org/edit/32230321

Keep in mind, I have reported this for months. I'm creating the bug mostly for proper tracking.