Doesn't genderfluidity undermine the entire point of having these gender labels in the first place?
It's like the kind of troll label I'd come up with, but they're using this shit in earnest.
Just to confuse y'all. I know a gender fluid person who hates being referred to as they/them, haha. His preference is 'he' or 'she', she doesn't mind either.
So while using they/them is the best way before you are aware which pronouns to use in general, you should always ask to make sure if you can.
In the case of a celebrity who has told us they'ew gender-fluid/non-binary and not stated their preferences, I would personally use they/them until clarified.
In this instance, Bella says she doesn't care which pronoun peope use. I also know people like this, just use any until you're informed otherwise.

isn't this problematic?
assholes who don't want to recognize her gender fluidity will just continue to call her "she," yet she's provided them the cover of saying that's ok
everyone including the media will just keep calling her "she" rather than alternating, because reinforcing the norm is more comfortable and important than recognizing her status in a minority group
and she says she's ok with this, completely denying the experience of everyone out there who has to struggle to get their pronouns recognized
it's like every girl out there who's like "tee hee I'm bi," wanting to be cute but not fully committing to the cause