Like atm you have teams running Bastion mirrors with the same old shield/healing stuff and it just isn't working and is kinda dice roll-y. I wanna see what people running things like Pharah/Genji/D.Va/Zarya etc. will do. I'll admit the thing isn't very fun to fight against doing the same old Rein shit, but I don't think people are ready at all to fight it after getting used to Rein/Ana metagame for 6+ months.
I think it's mad dumb Blizzard put it all out like this though. Even if it turns out to be balanced, the community reaction points to people not being able to handle it at all.