> Antifa is an organization

This one baffles me. Obviously it is - not a national one, but there are plenty of regional organizations/groups using that name[1][2] who share similar goals/methods. This is akin to saying that "Anonymous" didn't exist back in the day - even though you had people organizing on 4chan to do collective action (mostly against Scientology) under that banner.

[1] https://rosecityantifa.org

[2] https://theanarchistlibrary.org/library/forming-an-antifa-gr...