OK well, around the time these games got revealed, I can recall that there was a lot of fan outrage and fans were upset that it was Kanto for what was believed to be the 34958th time (with some claiming that the game shouldn't have existed and it was not worth the money), and it wasn't helped by the fact that it was dumbed down and catering towards the GO players. As time passed though, reception became a lot more neutral, and there was a point where people started getting hyped for the games, a far cry from the reveal period.
Now the games have been out, reception has been a lot more neutral. Sure, it's not at the hype levels of before, but not at the heavy fan outrage levels as before. I didn't really mind the game, I didn't mind the GO mechanics, my only issue with it is that it sticks too close to the first generation. It doesn't really do what FRLG did and expand the world, as a result it felt rather restrictive and the game was being designed to a restrictive map.