The amateur thing is a bit of myth to me. You can take the tuition, meal cards, stipend, swag, special tutors and preferential housing and call that payment in kind. Add to that the training, facilities, nutrition and sports medicine etc that they get, then they are & were pro in all but name. NIL makes is official (to me) and the transfer portal gives some power to the players whereas prior a coach basically had you by the short and curlies.
I don't know if the big two everywhere fund everything else, but probably do in some places. That's all due to title IX though, otherwise would the colleges really carry them all? e.g. What would the US Olympic Committee do if the colleges could drop them, given they basically have college sports providing them with all their athletes and success, same as NFL and NBA in the main.
Isn't title IX predicated on federal education funding, here's a whatif .. what if education is handed back to the states to administer and there is no direct federal funding (no dept of education), does that mean title IX is defunct and colleges can drop any sports they don't want anymore - what impact would that have?