The load factors will be watched like hawks by many for some time I am sure. If they are the same as when other types were used on those routes then the discussion is over. But the next major incident / accident involving one , even if not specifically technically related to the Max type will reopen the Pandora box.
But was the same after the 787 fires, people forget quickly if you give them the time .
2 years and a pandemic afterwards might be sufficient time , especially if the ticket prices are right...