There are some games where if you don't do the side quests, you find yourself under leveled and struggling. Happened to me in Witcher 2 even though I thought I had completed all of the side quests in an area. Had to go back to the previous area and grind some more.
IMO that's how it should be. I absolutely hate the games where I do all the side quests in a zone and still have to grind to continue the main quest in the next zone.
Real life is like the kind of games I hate. The side quests never give enough XP 😮💨