It wasnt clear from the blog so I'll ask here. Where does the money go? The post refers to providing tickets to underprivileged attendees, but is that 100% or ony some part of it? Where does the rest of the money go?
Attendees pay the Hotel directly for their rooms. If the event does not book enough rooms to cover expenses then the organizer (PyCon) owes a minimum amount to the Hotel. If there are more rooms booked than expected the Organizer gets a check. This is a normal Hotel industry arrangement.
PyCon itself is run by the Python Software Foundation; according to publicly-available records they spent approximately US$2,491,000 on PyCon US expenses in 2024, including supporting 552 travel grant recipients: https://www.python.org/psf/records/