So I have actually managed to put a good amount of play time into Pokemon Sun, and it has definitely been fun. I feel like the game designers have been really focused on player comforts in the past few generations of Pokemon games, and this one is no exception.
“back in the day” when I first started playing Pokemon you really had to work to get your party high enough level for each gym. Since they re-vamped the XP share (which I think was in X/Y?) I now find I actually have to be careful not to out level my story progress. I have even had to switch up my party just to be sure that certain Pokemon wouldn’t level so high that they stopped listening to me.
I know that there are definitely players who feel like these kinds of changes make the game “too easy” and I definitely do agree that it is not the same type of challenge it used to be. That being said I also know people who never finished Pokemon games before because they didn’t like the grinding type mechanics, who now really enjoy the game. I guess that’s one of the dangers of trying to broaden the audience. However, considering the sales numbers of Pokemon Sun/Moon I think that Game Freak knows what they are doing.