I see what looks like a bunch of Black Bloc anarchists. Are you sure they're idealistic demonstrators who oppose Fascism?
What do you think *antifa* is?
An identity/ideology defined exactly by the willingness to take direct action against fascist imposition.
What do you think it is? Because if you say anything other than "An identity/ideology defined exactly by the willingness to take direct action against fascist imposition", then you are wrong.
It is, entirely, along the same lines of furry: "an ideology/identity defined exactly as having an interest in anthropomorphics in art, media, and culture".
"Antifa" says nothing more, and nothing less than that the claimant of the identity is supportive of direct action against fascism.
Some Antifa believe all sorts of crazy things. I could as easily say "all conservatives are tRump Terrorists".
They are distinct identities. Even if 100% of dogfuckers were furries, it doesn't make the statement "furries are dogfuckers" true nor does it even make the statement "dogfuckers are furries" apt or appropriate, because furry is not defined in terms of dog fucking nor is dog fucking defined in terms of furries: a non-furry could be a dog fucker, it is merely accidental here in the hypothetical that they are not!
You just have absolutely zero legs to stand on in this argument.