Earlier quoted context omitted.
Right. I think I was unclear -- my point is that whether or not you agree with the E.O., you must surely agree it makes travel to the U.S. difficult for transgender travellers, right? And that's a problem for the conference.
Source?
[1] https://www.independent.co.uk/news/world/americas/marco-rubi...
If you're wondering why transgender travellers don't have documentation that matches their birth sex, it's because (gender identity aside) it's usually more important for documentation to match one's appearance. Documentation that doesn't match one's appearance can lead to questions, delays, and confusions. I have no source for this.
If you're wondering why it's a problem for the conference, I don't have a source for that either. But from the tech conferences I've been to, I generally have observed a higher proportion of apparently transgender people than baseline. So by hosting in the U.S., the conference could potentially miss out on many transgender foreigners participating.