I'm not sure how I feel about people arriving at Bastion, being forced to become Kyrians against their will and then having the possibility of just failing and becoming a reject because they didn't destroy who they were enough and are thus not virtuous enough for them. Heck they're even suggesting Uther doesn't actually get respite in this place after all he did. Also lol this zone of undead order and purity is literally at war and in chaos with it's own inhabitants, kinda an oxymoron there don't ya think Blizzard?
You're correct, the Shadowlands literally were just the mirrored world the player could see upon Death and explained why spirits and ghosts could stick around and how people can be resurrected or come back if they hadn't passed onto the "afterlife". Now they're retconned that to say the Shadowlands is the defacto afterlife and another realm entirely which completely botches all previous mentions that don't fit with spirits having "gone to the shadowlands" but still being able to come back.