Wanted to redirect @moid's point here, because there are some important & valid definitional issues at play. Ergo, #defining-fascism.
I find it easy to agree with claims made by other folks that fascism is actually pretty straightforward to define and diagnose. If you compare established definitions the themes and overlap should be obvious. Personally I think the perceived complexity of the task largely depends on whether your inquiry is rooted in a desire to protect those facing oppression from harm, or a fear of open conflict.
"How do you define fascist?"
They act in ways similar to how other fascists act. They act in ways that promote nationalism, authoritarianism, racism, sexism, bigotry, antisemitism, and/or support people and organizations that do the same. Those are fascists.
The fact that people are so worried about how to define fascists is because they want to know exactly how much of all of that behavior they can get away with before getting banned. So you start with "No Fascists Allowed". Tell them right up front NONE of that shit is allowed. If they're arguing about how you should allow a little of it, that's because they want to do a whole lot of it, so you just skip to the end and ban them.
No Fascists Allowed mens you don't have to allow fascists a platform to spread their garbage. You don't have to wait until they break a rule in your particular space. If you figure out they're a J6er or a Qanon or whatever just straight up ban them, even if they've never been caught doing shit in your space - because they will. Eventually. And you probably won't hear about it or see it until after they've already gotten a bunch of their friends into the space and already driven out a bunch of marginalized people.
Of course I could predict that use of the word would be painted as reactionary. Truth is, it took me many months to come to such a discernment. The anchor page in my knowledgebase is still titled "Holochain and Supremacism"- since that is a less inflammatory word, and these issues first began to affect me specifically as patriarchal / gendered violence. I am wary of extending harms that I experience as a trans person to other marginalised identities; though many are linked (eg. any LGBTQ+ gender expression threatens White racial hegemony).
But, now we have this body of evidence. I'll leave it to others to go through these lists of fascist ideologies and characteristics and tick off those they see in the above content. Maybe we could make it like a game of bingo. "How many times did you see 'dehumanization and scapegoating of marginalized or oppressed groups'?"
Harmful beliefs tend to come in clusters. Plenty of Moritz' close associates and the people he empowers are calling to "restore European civilization to the great path of our people" or denying the holocaust and saying that "Hitler had some good points". Moritz is out there broadcasting that all trans people are perverts and paedophiles. Call a spade a spade.