I stopped playing at expansion level 71, at that time I was still stuck at level 67 because to raise 1 level I needed ±100k exp. then I returned to playing at expansion level 81, and it was really easy at that time from level 67~level 81. it only took 1 day for Story quest+side quest+daily quest. I think it's normal and not a problem if the developer reduces the amount of exp gained.