If they went head to head at the beginning of the season that mean competing with the NFL AND the NCAA in football, and also the end of the baseball season. Nobody would watch them then either.
The fact is these leagues are born dead. I watched one XFL game the last time around out of morbid curiosity. And I barely made it through the whole game, the talent just wasn’t there.
It's tough market. The NFL has got generations of fan loyalty...not to the NFL but to teams. If they could convince a few whole teams to move to a new league they would have a shot. Probably the NFL contracts don't allow that...for example even if you took all the players and coaches from the Detroit Lions the NFL probably wouldn't let you call them the Detroit Lions.