It seems strange to me to argue the specifics of which criteria Trump needs to satisfy in order to start freaking out.
The scariest thing that Trump and Hitler have in common, from what I have seen, is not their character but the people that support them. The most important thing you need to be a successful fascist, or any kind of leader really, is not a particular kind of character but people who support you, or just don’t express disapproval.
That is why we are expressing our disapproval, and fear, and talking about how bad this could be—we are not trying to predict the future; we are trying to prevent it.