What kind of crazy excuse for a plan is this? It satisfies no-one.
The cellular side are concerned because they can't use C band at many airfields.
The aviation side are concerned because they don't have protection near many other airfields.
Are the unprotected airfields being used as an unwilling test case, with future regulations depending on whether there are many incidents at them over a period of time?
There are just too many variables of equipment, operation and terrain for such a plan to be adequate. A merely representative test based on a subset of conditions answers nothing. As observed above, aviation has never worked this way.
An issue on this scale, involving potential risks to life as well as billions of dollars, requires a properly organised test regime based on equipment specifications and actual worst-case physical operation.