WTF were they thinking
ufoi.org is a giant waste of everyone's time; a solution looking for a problem.
To not sign up to UFoI just do nothing.
No one will accept your membership to anything, nor will anyone publish your instance on a list to be targetted and associated with annoying opinionated instances that are worried there will be no one left to federate with unless they get everyone agreeing to not defederate from them.
Then, you can just carry on using the Fediverse as you always have, moderating your instance as you see fit. Because that is the point.