I don't know the percentage but if you look at the college commitment lists for the next four years on Collegegymfans it notes whether each girl is elite or level 10. Some of the schools are mainly elite recruits while other schools have none at all. https://www.collegegymfans.com/recruits-sp-367083677.html
Gymcastic did a breakdown of this a few weeks ago. Overall, about 20% of Division I gymnasts were "elites" at some point in time (but it looks like this list includes those who only did HOPES or a qualifier, those who tried elite and dropped back to L10, and those who competed at the elite level for a foreign country). If you are counting only those who competed at a U.S. Classic or Championships, the percentage is going to be much smaller.