The lack of a requirement to operate under a license will only make a mess of the available spectrum, exactly as it is with both 2.4 and 5.8 GHz wifi. In places where there are many competing WISPs, nothing actually works, because all of them are interfering with each others’ access points. The licenses should be essentially free, but at the same time the number of operators in a given area should be limited. The thing about rural areas is that there are not many potential customers there, so installing a 10.000$ professional radio relay for 10 customers is simply not viable. The hardware needs to be cheap, the license needs to be free and the company that would get the license should not have to worry about interference from their competition, because otherwise it’s not worth the WISP’s trouble and they drop those problematic locations quite quickly.