I think they are frightened, and have more or less decided that it’s time to make their move.
Trump isn’t dangerous, but he’s a symbol. Within an hour of his arrest, there will be a massive wave of other arrests and Biden will be retired.
They’re trying to make him a martyr so our side will get violent and give them an excuse to indulge their desire to arrest or kill US, to get absolute power. It’s called the top down-bottom up strategy.