I have seen demos. Years ago I even witnessed NHK's first showing of 8K with 22.2 surround. That was definitely amazing, so I'm not against this stuff at all.
However, demos are just that, demonstrations of the best scenario designed to present something in a way that highlights the best of the technology.
In some movies, it could really be a nice addition, especially in something from Marvel for instance.
Most of the time, IMO, it will be unneeded and draw attention to itself in a way that pulls one out of the story or be downright gimmicky.
The other issue is will enough people support DTS X or Dolby Atmos for that matter with the proper speaker setup, receiver, source, etc. for the studios to dedicate the man hours needed to let the magic come through on all but the select few productions? Or, will they instead cheap out and do the minimum to say it's in there and let the audiophiles and bleeding edgers duke it out on the Internet much like they're doing with 4K and 3D before that. Hell, some Blu-rays out there look marginally better than an upscaled DVD because the studios are so cheap.
I hope it takes off, because it is something that could be great. I'm just not so sure it can be profitable enough in our culture of mp3's and Netflix with Dolby 2.0 being enough for most. The one thing that may help is if it can really shine with back catalog movies that weren't mixed in the format and it can "enhance" the existing tracks in a beneficial way for those that may be willing to just upgrade a receiver in an existing theater.