Yes indeed. Non-binary means, kinda, opting out of gender. Some people might have surgery (I think a fair few chesty non-binary folk have their norks lopped) but if someone is biologically female and hasn’t been on blokeifying drugs there’s not the slightest issue with them competing in female sports. It is entirely unlike the more thorny matter of people biologically male competing in them (which, for the record, every single trans person/advocate who isn’t an idiot recognises is complex and necessitates rules based on physiology, not psychology).
Ms noodlé is non-binary and prefers they/them (and is absolutely not, in fact, a Ms) and has dumped the birth name in favour of something ambiguous. It’s a social change, not a medical/physical one.
I know they/them feels clunky… but, really, the ‘singular they’ is very ordinary indeed and everyone uses it often. We’ll get used to using it for people who we’d previously have used a gendered pronoun for.