I hope it's there. in NV, that was the only Hard Core feature that mattered to me: I could make up for all, but ammo weight meant that I had to regularly return to my home and strategically decide how and what weapons and ammo to take on following few quests. Food, water, sleep and even more health problems were all trivial.
But that's what hardcoe mode is about. having to micromanage our food, water, sleep, ammo, health, etc.
Higher difficulties are there to make it just harder.
I heard many complaints about NV but never ever did I hear anyone complaining about how hardcoe mode ruined the heavy weaponry.
Besides, it is unrealistic that some weakling with no muscles even uses them. Want them? Invest into your Strength or use PA, like everyone in FO-verse does. And don't carry more than one heavy weapon at a time: Survival/hardcoe Mode isn't supposed to make you cool or god-like.