They believe he won the “election” in that he should have been awarded the most electoral college delegates. They might argue that the electoral college voting of 2020 was invalid, but you can’t retroactively change the result.
Like, if Trump claimed to have called Shotgun first, but Biden actually called it first and then Biden got to ride in the front seat. On the ride back, you couldn’t say Trump can’t call shotgun because he rode in the front seat.
Trump wasn’t president, because he didn’t win. He still claims he should have won, but that’s both a lie and irrelevant to the Constitution. He could also claim to have been born in Ethiopia to foreign parents, which would also disqualify him from being President, but that would also be untrue and irrelevant.
He did incite and support a terrorist attack and attempted insurrection, which should disqualify Trump from holding any office, but we don’t have a functioning justice system.
That would depend on the LLM and the data used to train it.