To speculate on how it will affect RV'ing without knowing any details is simply idle chatter, and accomplishes nothing. No one knows what privatizing would do. Without that crystal ball you mentioned it's silly to groundlessly opine what would happen.
If the prices go through the roof I would imagine it would affect everyone to some degree, but if it didn't change overall, then not much will happen.
Let's not try to create rancor and division without actually having some serious information to put forth. The fact is that no one knows how their RV'ing will be affected because no one knows how Medicare costs will be affected.
