With lower frequencies comes much lower bandwidth. 5G networks can transmit at much higher power than WiFi, so that's where you get your range at higher frequencie - however that requires licensed spectrum which makes all this a bit harder.

Use the networks for what?

Maybe I've just been out of school for too long, but I can't think of anything particularly interesting a campus would want an IoT network for beyond maybe motion sensing for automatic light turn-offs and run-of-the-mill security systems.

I can't imagine a low-frequency IoT network being good for broadband access for people walking around (a la wifi) because of bandwidth limitations.