They should simply have awarded less XP for things....on my second playthrough (which I have abandoned due to boredom) I was max level again about 50% the way through Act 3, even though I skipped a lot of content that I did in my 1st playthrough. You certainly don't need to go to high levels - Bg1 showed that. I never had a issue with stopping at level 7/8 or whatever it was. Same with BG2/ToB, IWD etc - the encounters seemed to work well within those constraints. In BG3 XPs are handed out like candy - along with excessive amounts of loot (way too much for a 5e game). There is simply too much of *everything* which means you don't appreciate XPs, or items, or scrolls/potions. Even playing on Tactician doesn't change this much.
