This example makes literally no sense in this context, but I'll give you one that works better:
2 guards in front of a safe at a bank. You are a thief who is trying to steal what's inside the safe. You are a really horrible thief, so instead of sneaking past them or whatever, you run straight up to them and try to fight them.
Now, in this scenario, do you expect the guards to just auto attack you? Were they hired for this job because they're completely incompetent? Nah, they're probably pretty proficient at ensuring that the safe is shut tight. So, I assume they'd be a bit more... mechanics based. Maybe instead of just gently slapping you, they pull out their guns and start firing at you. In the real world this would require you think on the fly as to not die, but in a game this would be replaced with a "mechanic". Even in the game scenario where it's part of a crew of pirates, you wouldn't stick two random guys in front of the door to the chamber of the Kraken. As an easy example, there is a mob in the very next room that can chain a party member and then cast an AOE. This would've been a good idea in the 2-man room, but instead we have auto attacks.
Also I'd like to say I do like the rest of the dungeon, it's not fantastic or anything but it was pretty good the first time I ran through it. The first and second bosses are fantastic and I hope we get more bosses like that in future 4man dungeons. This part of it just stood out for me, as did the small room in Snowcloak. It is a small complaint, but does that somehow make it pointless? Nah, I don't think it does really. Most requests SE gets are "quality of life" changes, and usually when they're implemented a lot of people are happy about it. I'd be happy if they just made the walls consistently interesting.
You did answer my questions, but they weren't really... answers. You kinda just said "well, the original had 2 mobs, clearly the HM should have 2 mobs as well because blah blah blah guards blah blah blah". I get that they're guards, but maybe the guards in the HM shouldn't be equally as weak as the ones in NM.