Tags IsBaby and IsVillager can't be changed from true to false with /entitydata

The same happens with baby Zombie Pigmens and trying to do:

/entitydata @e[type=PigZombie] {IsBaby:0}

WAI per Searge:

Please do not report issues related to NBT tags as bugs. If changing NBT via commands does not have the expected effect, that's always considered "working as intended".

As someone on the subreddit pointed out, entitydata hasn't been a command for awhile. Both entitydata and blockdata were replaced by /data. But from the console message he got I can see he used the right command in-game.

EDIT: also most baby creatures (the ones that aren't undead at least) also have an age timer with a negative value. When it reaches zero that causes them to turn to adults and now that the timer is into the positive numbers it's "age" is how long it's been an adult. Undead don't grow up (aging is a side effect of the wear-and-tear damage of being alive) and so baby undead don't use this timer. Presumably this is why changing its "IsBaby" tag isn't enough.

@unknown Why are you speculating on a bug that has already been fixed? Of course entitydata isn't around anymore, the obvious explanation is that the same bug was present with data merge.