Oh I agree, and do not believe anyone can "make" someone be, or feel anything. But children are frequently influenced and shaped by their parents and their environment. Nature or nurture, oldest argument around. One will win out, but I do not believe an 8 year old can understand the complexities involved with a pronoun such as they without some guidance from an adult. Thats nurture. JMO.
As far as perverse, maybe I could have used a different word but no, I do not see what Emily is so proud of. As a straight female and mother of four I can never imagine myself posting "I'm so proud of Susie. She likes boys, and wants everyone to call her her!" Or- "I found a Playboy in Johnnys room! I asked and he's straight! Woo hoo!!" Nope, dont get it the pride in those, or Emilys announcement or see the need to make them.
Her insta may be set to private, but it sure ended up here. And if her "friends" list reads like most peoples....old school buddies, former co-workers, childhood friends, etc., do any of them need to know her daughters preference? Likely not.