Often completely missing from this debate is the concept that context matters. Sometimes, in casual contexts, it really doesn't matter what someone's sex or gender is, so you may as well address them using the gender terms they prefer, just as you would address them by the name they prefer. If someone looks like a woman, and the context is a casual conversation in the office, then it would be a bit mad to call them he/him, even if they don't really pass, because (a) it's rude, and (b) you don't have a way of
absolutely confirming their sex. So, casually, it seems like we should treat trans women as women.
But then some contexts aren't casual, and a person's sex really does matter. It would be equally mad to exclude trans women from prostate cancer screenings, for example, when they are unambiguously male. Given what we know about male pattern offending, granting males (regardless of their gender identity) access to intimate female spaces creates risks that many females would rather not take. Given what we know about male physique and the impact of testosterone, granting males (regardless of their gender identity) access to women's sports creates injury risk and unfairness. So, in these not-so-casual contexts, sex trumps gender and it seems we should treat trans women as men.
Personally, I think a sex offender's sex is absolutely relevant to their crime and thus relevant in a Wikipedia article about their crime - and it's genuinely absurd to read about a male rapist and "her" victim, besides being grossly offensive to women in general. This is not a casual context, and the polite fiction should not take precedent.