Yes, attempted and declined by more than just Boeheim. That said, it is my perception that a legal argument would be an uphill battle for the NCAA.
They are saying "it's not a fifth year", but kids are playing five years and had more access to compensation than this small group of excluded players (Ivy League). The exclusion occurred due to a decision that was made for them. The other kids played in front of fans during the 20-21 season and everybody made money (the NCAA, the schools, the arenas, etc). They can say it's not a 5th year all they want, but that's going to be tough legal argument.
The Ivy League players are being treated differently based on arbitrary and capricious reasons. And, that inequity is having a fiscal impact. Good luck in court.