It's mostly to do with the fact that they've got a WWI game in which maybe 2-3% of the players are using unscoped bolt action rifles. That's the single greatest factor that can set a WWI game apart from the usual fare and they didn't even bother trying. What it honestly should have been was for that to be the standard on all classes, with assaults also getting access to trench guns, the LMG class also getting access to those (built in a way that makes them useful as LMGs, rather than very inaccurate assault rifles). Recon get their scopes (and I'd also give them the semi-automatic carbines, sans large scopes, to let them fill the role without camping at the edge of the map, but drop the damage so that their TTK is higher than an accurate bolt action shot), medics get rifle grenades (and maybe also give them and recon better pistols).
There. You've now got >50% of the players using bolt-action rifles, most without scopes. I'd bet most people wouldn't even bitch too much about it. They certainly didn't back when Coddlefield games had unscoped bolt actions before, those saw plenty of use.
As it stands they really should have just made it an alt-history steampunk game if they wanted everyone in "WWI" to have submachine guns and semiautomatic rifles. Or made another WWII game. :V