I'm not sure this line of argument works. If a website is on board with the idea of allowing disposable email, then why are they even requiring an email address in the first place? Signing up for golangnews doesn't require one, and discovering that was a breath of fresh air.

By analogy, if you feel the need to give somebody a fake phone number, then chances are something had gone sideways in your interaction with that person well before you got to that point.

If on the other hand, a site is using email addresses as a form of pseudo spam mitigation or identity verification, then detecting which addresses are disposable could be a useful metric to log about new users.