I will admit having heavy Crowd Control characters can alleviate this issue a bit, but a lot of us are veterans, and even WITH the heavy CC characters it's noticeably harder. I used Max forged Tolchock Konstantin with his rare heal card for 25 health a kill. And I was killing mooks on the final phase NON STOP and they were still swarming more than I could handle. I noticed this with Kuzman to, I RUN OUT of ammo with Kuzzie on this phase. BUT, in solo queue it is not that bad.
the worst for me was this issue on Hanging by a thread, this tilted me to never group again. We lost so bad, a bunch of veterans 4 stack, to a difficulty of about 40ish...I looked at the damage it was insane. We broke group under a bad mood and never grouped again. I don't make squads anymore because of the hidden difficulty the game punishes you with for grouping. Until they admit this was an issue and fix it, I will not group and will recommend others shouldn't either until this is fixed.