Why does nobody in pubs respect the MG-43

I'm pretty new, only level 22, but I've grown in love with the MG-43, its just so versatile and powerful. Yet every time I join a pub when my friends are busy, It's 90% of the time, "Newbie Weapon", "Not Meta", "You aren't contributing". Yet ingame combined with an engineering kit armor i literally just go prone and stop entire waves in their tracks. Beyond the usual "whatever suits you best" is there really anything wrong with the MG-43 as a weapon?