Hey there,
So the problem I have has to do with damage reduction, or rather the lack of it.
I do understand that in d&d armor class means evasion really and damage reduction is achieved by evading. But it is immersion breaking beyond believe when my bareass naked mage takes the same damage from a hit as my heavy armored dwarf.
But you don't think it's immersion breaking when someone has 100hp and takes multiple massive cuts from a Greatsword to go unconscious? That's what we are also seeing in BG3.
You have to understand the whole HP - AC - Damage is a massive abstraction. It does not emulate realism. A "miss" against AC in D&D means dodging or blocking or armor absorbing the blow. Likewise a "hit" in this game system doesn't mean your weapon cuts the enemy. It could mean they block the weapon but get punched in the face, or deflect the hit just enough to make it a grazing wound. When someone has high HP it's more like stamina. And when that stamina runs out you can make a finishing blow against someone who has been cut and bruised, but not lethally.
Of course, it doesn't help that Larian have failed to present either case, hits or misses, properly. Their misses are always clean misses where a tanky enemy dodges like a butterfly, and their hits are massive cuts that create pools of blood everywhere for gimmicky freeze/electrify purposes.
So yeah, it's the game's fault for making players feel something is wrong.