Legacy scaling is indeed up…but absolutely messed up.
https://us.forums.blizzard.com/en/wow/t/old-raids-no-longer-soloable/676822/190
First image is myself with no corruption soloing Mythic goroth while never dropping below 50% hp on patch 8.3, second is on prepatch with exact same gear. You can’t even argue its due to corruption or that Ion’s post on twitter is being honest. C’mon, its a blatant lie no matter how you put it.