If time is the only measure then it's a stupid question. Forget who has won the most championship medals. Running is only a time trial. Tactics and competition mean nothing. Who you beat and how big an occasion is what racing is about - otherwise runners have no reason to line up against each other on the track.
Who won the Millrose mile today?
Who did he beat, apart from his pacemaker? And this ranks up there with World Championship or Olympic titles - of which he has none? And how many of these titles does Farah have?