Oh, I don't know about that at all. The movie "Heat" was pretty realistic and it was very good. That's just off the top of my head.
There is also a limit to "lack realism". That limit tends to be suspension of disbelief, which in turn relies on a coherent narrative structure and consequences within that structure.
To wit: Jedi are pretty unbelievable, right? The Force, telekinesis, light sabers, etc. But the movie sets limits on them, makes it clear some of the things they can and cannot do. If you'd seen Luke cut the Death Star in half with his light saber, how would that have looked? And then teleported home from his X Wing? Pretty unbelievable and silly, right? I mean, if they could do THAT, why not just do it from the get-go?
Your players may have travelled light, but what if they discovered they could layer on oft and hard armours, carry an Anti Matter Rifle, forty grenades, a spare Deck for the Runner, a primary and back up secured phone, extra cyber-limbs...and all of that fits in their duffle? Players do that because they like to survive - and also because they are pack rats.
Lastly, rarity typically increases value. If the PCs can carry an SMG, shotgun, two assault rifles, three handguns then they won't really value any of them. If you tell them they have room for one long arm and two short, their sense of value of those weapons will go way up.