Depends on the game. I’m still a very long ways away from completing it, so please no spoilers, but Sonic Frontiers? They added enough to the open world that it’s fun to run around and do side stuff in. Pokemon Violet? The charm wore out quick enough, making the region feel way too empty compared to most other gens, so no. No clue on the DLC, but I imagine they’re similarly as empty and devoid of NPCs as well. Games like VoxeLibre on Luanti? Wouldn’t want it any other way!