I liked being able to visit Kanto on those games and I would like to start being able to visit previous regions again. Although my feelings on the matter are actually a bit mixed. On one hand it would be nice but on the other hand I would prefer having larger regions with more in them to explore and it would be hard for them to do both.
On another discord server I was in we had a pretty interesting and lengthy discussion on this sort of thing. Considering the Switch has the ability to power large, beautiful games like BOTW and Xenoblade Chronicles 2, I doubt TPC couldn't do the same thing here that they did for Gen 2/HG/SS, and I honestly hope they really do that again.