I think one reason is that in these movies those actors you mention are the “heroes” of the story, in the sense that they’re the ones who undergoe the transformation. The flip side, all the people who have lost everything because of Belfort are not portraited at all.

Another reason might be that many people are simply greedy and the consequences for the main actors weren’t that bad in the end after all. I think the real Belfort made an appearance at the end of the movie and gives speeches nowadays...