This comes to us from BossLogic, who has become associated with mocking up fan castings, rumored castings or recently announced castings for major franchise movies.
Setting that aside, Mahershala Ali is exactly the type of talent that Marvel Studios is able to attract these days.
Not that it should come as a surprise to anyone familiar with Mahershala Ali, but it works quite well as presented.
So Ali probably wouldn’t have any reservations in signing on for a major franchise like this, assuming it felt right.