The labels are fucked anyway. They'll get a few solo stans supporting each of their members but fanbases support groups, not individuals. That's why every post Produce group has flopped. Wonyoung could see some moderate success as a CF queen, her and Yujin's Starship group could have some minimal success. Yena is becoming a variety show queen and Minju could achieve some moderate success as a model/actress. But if the labels think their new GGs are gonna blow up because Izone sold almost 3M albums in 2.5 years...they're gonna be in for a world of hurt.
Add up Starship NGG, WM NGG, 8D NGG, Rocket Punch, Everglow, and every other NGG that forms from Izone members, these groups wont even sell a third of Izone's sales even if you combined them all together.
A lot of people forget that they are still sharing the sales with the other companies minus the part cjem gets. I think that even though all the other groups have flopped they can still get as much money if they act fast and promote them better than the others. Solos like Chungha showed that one can be successful if promoted intelligently and fastly before the izone hype is over