It’s obviously a common vernacular simplification from authoritarian with a broad definition. This is a commonplace and accepted vernacular in most modern western media based social media outlets.
Fascist can be liberal, they can also be conservative. Or communist. Or almost anything. More often fascists will lie and say they are more socialist than many of their policies would lead you to reasonably expect.
Grown ups are talking. Go play outside. You obviously need to touch grass, child.