He may vacate the Oval Office and everything that comes with it on January 20th. But that doesn't mean concession.
He will be leaving Biden with an eternal asterisk beside his name in the history books. No serious scholar in decades to come will be able to think of Joseph Biden without also noting the dubious circumstances of his "election".
No matter the outcome, Trump has won this. Perhaps not in the ways of modern politics, but in the larger game he is going to come out the clear victor.
You don't concede an election you won.
If SCOTUS determines Biden won by election fraud a year from now, will Trump be installed as president?