Every year BYU had to turn down multiple requests from so many other sports wanting the same deal that hockey had. Admin was sick of having to deal with that and finally decided the easiest thing to do was to just get rid of that deal with the hockey program.

Even though they "sponsored" the team, they didn't have much control over it at all (or any control?) and many players were not really BYU students (or fully matriculated) students. Admin had a problem with people representing the school that weren't really students.

A few other smaller reasons. But those 2 were the deciding factors.