No buts about it, the tide is turned when the candidate(s) concedes and urges their followers to accept that they lost, and to move on with reality. That is one of the worst things he did to the country, but as far as I know not conceding is not a crime either. But as the Majority leader in the Senate said in Feb 2021,
“There’s no question — none — that President Trump is practically and morally responsible for provoking the events of the day. No question about it. The people who stormed this building believed they were acting on the wishes and instructions of their president,” McConnell said. “The leader of the free world cannot spend weeks thundering that shadowy forces are stealing our country and then feign surprise when people believe him and do reckless things.”
IMO when the Trump Republicans refused the bipartisan commission, 9-11 style, to investigate Jan 6th and the events surrounding it, the DOJ should have appoint a Special Prosecutor then.