I don't think anyone is disparaging the MED. It's more an issue with GC petitioning to play down several times over the past 30 years. Future enrollment will likely justify them being in Class 1 but they squarely fall within Class 2 parameters right now and petitioned VHSL to play down in Class 1. When the New River District dissolved, the Three Rivers District should have been the AA district and the MED the A district but again, GC fought to remain in the MED so they could play smaller schools.
As for the nosedive in Grayson County enrollment, county leaders have made misstep after misstep in county management dating back to the 90's. It's not a coincidence that the county population is getting significantly older and speaks with a northern accent. As more and more transplants retire to Grayson County, locals with families needing employment will continue to be priced out (see Avery County, NC). Local families will continue to relocate and GC school enrollment will continue to shrink.