Please. Captcha by default. Email domain filters. Auto-block federation from servers that don’t respect. By default. Urgent.
And yes, to refute some comments, this publication is being upvoted by bots. A single computer was needed, not “thousands of dollars” spent.
Isn’t this what all you lemmy-worlders got mad at Beehaw for doing? I don’t think it’s unreasonable to ask for a small statement from people as an anti-spam measure (a sort of advanced captcha), though of course the big problem there is reviewing all the applications in a timely manner. Still, I think there’s room for more and less exclusive instances. The tools are there for instance owners to protect their instances however they choose.