Regarding PVE discussion in DMZ, Marathon's PVE test was a bit illuminating:
-"Sweats" are able to get better gear and curbstomp casuals quicker/harder than before
-PVE is/can get pretty boring in a game not really made for PVE
I guess people just want to play their game without some assholes coming and ruining your day. I get why people like extraction games but not everyone is a highly skilled, competitive player (sweat) and those people ruin games for other people (casuals)