Yeah, that’s partly why I said they don’t follow it consistently!
The important thing is that they have established a line now.
They banned trump because he was genuinely inciting real, imminent violence. Not just hateful rhetoric or propaganda, or even the kind of generic "death to xxx" you might see from some religious extremists, he was inciting real, happening violence by encouraging the rioters while it happened and then made statements they felt would lead to future violence.
They laid out their reasoning very clearly and now we just have to hold them to upkeeping that standard for any other heads of state / political figures.