I still remember knights of the old republic, if you found a vent to avoid a combat encounter? XP. Hacked that computer to kill the guards in the next room? XP. Talked your way past without incident? XP. None of this DOS2 nonsense needed where you're essentially encouraged to do everything, and THEN go back and massacre everyone.
I hope BG3 is similar, and lets people get XP for achieving a goal, regardless of how it was achieved.
That is my hope, too. In the EA, however, we can't judge the main quest because we did not achieve our main goal, and sidequests give no or insignificant quest xp as far as I recall. Granted, I didn't pay close attention to the xp rewards at that time.