Is it that simple? Because if you allow people to self-identify and mandate this must be accepted prima-facie, wouldn't it be very easy for any man to be sent to a woman's prison simply by lying? And I do mean sociopathic men rather than trans-women. This would not only undermine the safety of women in said prison but it would also very much undermine the safety of Trans-women who have committed a crime but should be placed in a female prison. They are likely to be hoiked out and placed in a male prison in the ensuing shit-storm. There is nuance here that you're not acknowledging because, as I've said in the article, any attempt to wave the nuance flag gets an immediate accusation of transphobia.