Some of the best regarded actors in terms of sincerity and generosity are actors who notoriously play villains, like all of the stories about how Alan Rickman was on the set of Harry Potter, he played Snape in the movies and his breakout role was as Hans Gruber in Die Hard, but to the Harry Potter kids he was their favorite mentor and they have quite a few stories about him that they’ve shared with the public since Alan’s death in 2016.
Playing a villain is hard when you’re not that sort of person, that’s why actors treat playing a villain as a challenge, and why the villain role is treated with prestige. However, that’s acting, acting is the art of transforming yourself into somebody else, and some people simply do it far better than others, and some people simply aren’t acting that’s just who they are, only history will spot the difference.