Microwave links provide up to 10 Gbps in perfect weather, but bandwidth is reduced by humidity or rain (
Microwave Link - Gigabit Microwave Connectivity). Fiberoptic can provide 10 Gbps on a single cable with a range of 3 km (
Fiber Optic Cable). The downside of fiberoptic is frequent amplification, so over long distances microwaves can be more efficient, but over the 3 km scale of a campus, fiberoptic is far cheaper and higher quality. Also less likely to be disrupted by storms, although more likely to be cut by construction crews; but if you make a fiber ring so there are multiple paths, that risk goes away too.
The one big advantage of microwave is that it is more portable -- as the first link says, "Speed of deployment and flexibility – the ability to move sites or provision rapidly – are greatly in favour of MW radio over fibre and cabled alternatives." You can put microwave on a truck, but you can't tether a truck to a studio with a fiberoptic cable and have it drive very far. But if you have fixed stadium sites, fixed campus uplink site, and fixed central ESPN studio, you don't need mobility.
Better yet, buy one of those used trucks and put the equipment in a room connected to the stadiums by fiberoptic cable. Presto!