I don't think we need them to make the game 100% 5e compliant. We just don't want them to make something else clearly worse when they make a change away from 5e.
Example:
a) Quickened spell doesn't shouldn't allow you to cast 2 spells in a round of combat. It should just be 1 spell, 1 cantrip. No one seems to complain about this as it isn't really hurting another aspect of the game.
b) On the other hand. The racial change has people up in arms because instead of choosing the pros and cons of elf vs half-elf. You are now taking away all the pros of half-elf so there isn't anything to weigh the decision against. (I suppose this issue also has lore-based complaints as well)
My biggest concern is that rumor of changing the way spells are learned when you multiclass. Right now, you have to weigh the opportunity cost and that makes it fun. If they just give you all the spells anyway, then they've removed the cons of multiclassing and left single classes with no advantages, and there just isn't a choice anymore. One is clearly better than the other.
