I have experienced the exact same thing on several old accounts. One was just completely ghost banned out of the blue. No warning, no temp ban, no suspension notice. The account just ceased to exist one day. It was also my least anonymous work account so I was definitely well behaved on it. I legitimately have no fucking clue what happened.

My oldest account (14 years now) has gotten two temp suspensions completely idiotic reasons, both of which were overturned on appeal, but I assume that still counts as two strikes.