Dungeons focus too much on Dmg for Challenge
When you’re fighting more mobs at once & mobs that do more damage, the tactics certainly change. Forcing you to deal with a lot of mobs skillfully is a good thing in this game, as it offers a lot of potential for both group coordination and individual player skill.
A lot of stuff changes as you get higher difficulty, and it really isn’t just damage. Even some of the mini events get harder: In volcano, the grawl that push the villagers off the ledge spawn faster / move faster as difficulty goes up. The dolphin swimming event in the underwater fractal gets a lot more hectic. The Cliffside seal breaking events get really intense with more mobs at once.
The difficulty scaling covers a lot of bases, and I think they’ve done a pretty good job preventing any single strategy from being the only strategy. To me, that means the difficulty scaling is working really well, since your approach will vary based on your group.