They don't need reporters, coaches have guys checking it daily. I'm fine with cracking down on the media access to it to be honest - plenty of kids announce it themselves so if they think their name is lost in the portal they can still throw it out on twitter or tip off a reporter. But the portal itself is supposed to be where coaches can see everyone available, not twitter.
I think it's a privacy thing, the athletes aren't obligated to let the public know their plans to transfer any more than a regular student. Many of them want to and still can, but reporters scouring the portal and student directories is a bit much for me.