I’ve seen a lot of people say that increasing enemy health to increase difficulty is bad game design. This is true, but only after a point. Nightmare to Cataclysm was a major increase in difficulty in game 1, not only because enemies hit harder, but because they stuck around longer to deal damage. By increasing the health of slave rats just a little, so that most weapons took 2 hits to slay them, Cataclysm totally changed how you fought hoards. You had to combine killing power AND crowd control, or risk getting overwhelmed by the rats you thought you just killed.
VT2 took a step backwards here. By giving players so much damage, and slaves so little health, DPS is the only thing that matters for a successful Legend run. No need for a shield and careful pushes when every swing, from every player, kills 3+ mobs.
Vermintide has game mechanics that allow a skilled party to never take damage in melee, outside of specials. Increasing enemy damage only punishes you more for your mistakes, which is all well and good, but it doesn’t actually make you approach the game any differently.