Anyone can be replaced.
Maybe at some point, sure. But there’s a reason Marvel agreed on a big payout for RDJ to come as Tony Stark Iron Man. It’s because right now, he’s the only one the people want. The people decided he was the best yesterday. And he rewarded them with…well…himself in return.
Anyway, after enjoying that video, I just lost half an hour to Robert Downey Jr on YouTube, revisiting some of his award show greatest hits, like when he co-presented with Tina Fey at the Oscars. These two need to be in a movie together, please.