> "The guy has clearly lost it and thus is probably not making sensible decisions"

That isn't the problem though. Fascism isn't mental instability, it's an ideology. Someone going off the deep end and making bad decisions does so essentially at random, while someone driven by ideology messes things up in very specific ways. In the case of Fascist ideology, the specific ways they ruin things are specifically intended to harm specific groups of people, so I think the distinction matters. Writing it off as the guy having "lost it" obscures the specific goal he is working towards.