There's a whole lot of things that can count as "unusual" that aren't spoofing, and telling people not to be super vague "unusual" is a terrible solution.
Ad block, other blocking, third party cookie restrictions, all the stuff firefox changes when you toggle resistFingerprinting. From your other comment "users with no google cookies" and "connecting from VPN".
Punishing people for not having Google cookies is probably the most obnoxious one.
