Why was this question(https://english.stackexchange.com/questions/225083/on-referring-to-a-specific-definite-person-whose-gender-is-known-as-they) voted to be put on hold as being POB by a user while his question(English parts of speech — better new treatments) is far from being objective? I smell double standard.
Questions about whether a particular usage is considered acceptable are entirely answerable, even from a descriptivist point of view: "In 2013 a majority of the usage panel at Murgatroyd's Unabridged Dictionary considered this to be an acceptable construction," would be a fine answer. "In this Language Log post from last August, Prof. John Frink stated that 'opinions about this particular permutation are still very much up in the air,'" would be another. An answer might note an apparent lack of scholarship on the topic, but propose a course of action based upon similar usage trends. Or one might simply note that there is no consensus to be found, and that would be the answer.
In a very real sense, all of usage is about opinions. Just because a question involves opinions in some way doesn't make it POB. That ain't what it's for.
The question should be reopened.