The issue is that when people start abusing words like "fascism" out of context they make those words lose meaning.

The US is definitely undergoing authoritarian tendencies, but it remains structurally constrained by separation of powers, federalism, and independent courts and media, features that fascist regimes systematically dismantle.

If you start calling everything fascism you are essentially helping those you call fascists because they can easily refute your thesis and gaslight you on the very realities of the authoritarian descent the country is going through.