I’ll be interested to see if 3D is still a thing by that point in time.
Probably not any more or less than it is right now. The main point of 3D from a financial perspective was to help offset the expensive conversion from film projection to digital. The studios and theaters realize there’s still an audience for 3D, though. There’s just not a particularly big one, which is why you’ll see less 3D showtimes now and mostly normal 2D.
3D is all the rage in certain parts of the world outside the US, though. That’s probably the big reason why the studios continue to spend the extra money in post on these big budget productions to convert them. Otherwise it wouldn’t really be worth it for them.