Board Thread:General Discussion/@comment-26937472-20160119102415/@comment-8986886-20160121034743

Wri-El wrote:4. Maybe Yhwach has the means to brainwash the minds of arrancars, also he might be able to use his powers to somehow allow hollows to use quincy necklaces, but I believe that the full extinction of it.

Why not apply the same logic here, as you did with #1? If Yhwach wanted/were able to brainwash Harribel, wouldn't he have done so already? Then there would be no reason to keep her in chains.