MCU is trying it's best to get back in the game. They are so desperate. We have to understand this. They lost their way with this saga. They planned so many projects and shelved more than half of them because they know that it's not gonna work. They shelved the whole Kang story into a dumpster. Marvel literally went into panic mode when all the films were failing at the box office and they need something big to get the hype up and to get back on the road again. So, finally this is what they agreed on and thought it be best to bring jr back. It makes sense. I honestly don't know what kind of backstory they will cook for tony stark as doctor doom.