Here's the thing, tho. Disney has kept the MCU going for 10 years without going the "legacy character" route once (with the technical exception of Ant-Man, but even that was backstory, not primary plot). Instead, they've used the massive library of heroes they have available to introduce new characters. If they were following that route, we'd have seen a new Iron Man by now (RDJ is 54). But instead, we got a different hero in a high-tech suit.