@lossless_autumn no, not at all! As I've stated: blocking TOR should not be done. Blocking temp E-mail providers should at least be an option from within the Mastodon interface.
Possibly it should be one of the two: blocking temp E-Mails or having a CAPTCHA. This way people who try to remain anonymous can still use this awesome network without also letting in spammers.
There are many methods and if one really tries we can block spam without limiting anonymity!