There are always bad apples in any fandom or large group. Even if 1% of people are bad, then any group that has more than 300 people is exceedingly likely to have one.
Yiff is specifically supposed to be for adult circles that enjoy it. If proper care isn't taken to protect youngsters from it, that's unacceptable, and I personally don't care for it, but I also don't care how other adults live their lives.
I support anti-furries up to the point where they keep furries accountable for properly protecting children. Directly opposing furries' existence as a whole is a little much, but a healthy dose of accountability is beneficial, if not necessary.
There are plenty of family-friendly furry circles, and they're amazing. But I do see the need for areas of the fandom that sort of "grow up" with the people who are part of it. Some of that isn't for everyone, myself included, but there are certainly people who *do* enjoy it, and that's fine by me, as long as proper precautions are put in place.
It does, however, have no place on this stream, and the moderation team is here to make sure it doesn't get through.