Re: For how long will the MCU go?
I don't think the MCU will be rebooted. It will be *recast*, but there won't be an actual reboot. Feige has said, time and again, that they will try and follow a Bond model.
As for how long things will remain popular? Honestly, I suspect the sky is the limit; as long as they keep producing good movies, people will keep going to them.