>>41909964They considered a reunion movie for movie 20 and abandoned the idea because they realized how many old characters they would have to bring back. Remember this was in 2017 so we were already a year into SM, so they would have to bring back about 10+ old characters for a movie and it was never going to happen.
They're never going to reunite all the main characters at the same time, there's way too many older main characters now. The last time that would have been feasible is when DP was airing, since it would have just been Misty/May/Dawn and Brock, and if they wanted they could have ignored Tracey/Max, but now there's too many.