People come at this one case as if success was a foregone conclusion. This level of financial success was absolutely not a sure thing for a movie made by 2 YouTubers, even if it was good. Plenty of people would negotiate away their equity stake for an increased wage (which would be a good choice in many cases), and some of them would then complain afterwards if it succeeded. Plenty of movies flop. As a person whose work cannot guarantee it even primarily influence success or failure, it makes no sense to trade guaranteed wages for equity in most cases.