Antifa doesn't really exist? Please explain people waving antifa flags, wearing antifa badges / clothing, putting antifa in their social media profiles? With this kind of logic, no terrorist group really exists.
They might as well be called "Anonymous".
Also, just FYI, one of the more prominent early members of the hacker collective anonymous was a federal informant named Aubrey Cottle (aka Kirtaner) who was a long-time Something Awful forum member with a very sordid past. Anonymous really wasn't that anonymous - it was full of feds and essentially a psyop.
The idea that they can find the folks organizing and funding these "cells" is a big part of the US gov's premise on how it is going to "fight" these "cells".
It's not stated as explicitly as that, so it's not surprising that folks don't pick up on that distinction between "distributed groups who agree on principle but don't have any material connections" and "top down, hierarchical structures funded by singlular sources".
But the folks running the US gov don't even see the folks who disagree with them as human, much less as having a legible and understandable grievance. So it's not surprising to me that they just project their own authoritarian and top-down organizational preferences onto other groups of humans doing stuff.
So sure, "antifa" exists. But it's categorically different than how the US government is trying to say it exists, and that's an important distinction.
Sometimes it helps to ask clarifying questions like "what do you mean they don't exist?" instead of assuming their perspective is the same as yours, and then sending a reply that doesn't make sense... that's a very easy way to start an argument.
But instead of unprofessional and rude comments like the equivalent of "people should just be smarter"... instead we can either educate people on how to communicate more clearly, or simply ask follow-up questions without resorting to attacks or assumptions.
Trying to educate anyone in anything on this website is a hopeless cause. Typing anything that contradicts a popularly held belief, even when true, earns downvotes into oblivion. People on this platform don't want to learn anything - people want to prop up the status quo, control narratives and further enlarge their already giant egos.