
My guess is it was the NCAA. Recent Supreme Court cases ruled that colleges are now allowed to pay their athletes, striking down previous NCAA restrictions that banned pay. This order is probably seeking to prevent athletes from transferring all over in exchange for whatever the best pay is, like what happened before the NCAA.
Looks like they’ve basically acknowledged they’ve lobbied for this “Asked why the NCAA needs an executive order to help solve its issues, Baker said, "On some of these issues, it's hard for us to do this without at least some support from the feds. The courts are one way to settle the debate, but it takes a really long time, and it creates a lot of uncertainty."”