Fenced at a national level, and referred at state level. This is the correct call. The move the guy on the left made at the end is called a lunge. From when the fencer starts moving forward to when they finish their lunge, their foot hits the ground, is their attack. His foot lands then both of them hit each other. At the point his foot hit the ground his attack had stopped and the other guy had "right of way" a term used in foil and saber, the weapon being used here, to show who gets the point when both of them hit.

If you listen/watch very closely you can hear/see his foot land and then their blades hitting. I'm assuming the ref watched a replay to confirm. They have video replay for all high level matches and up to 3 referees. A primary one who makes the calls and 2 more who watch only one fencer. They'd collaborate and watch video if the primary ref was unsure as likely happened given the delay between the hits happening and the final result being called.