It's a vicious circle, You know. The basis of all is that GTs are not suitable for anything but particular friendly conditions. No matter which rules You create they will always stay a minority on the side of the main rally course just because of that.

For the very same reason there are no manufacturers interested in GT category. Why shall they be when they know that only a total redesign of the whole car can make it fast on gravel or snow?

The FIA rules are seen here as more important than they are as they neither create nor remove the main issue which I just named. No rules can do that and in the same time keep cost affordable.

Dimviii wrote that maybe in harsh way but he is right and it's not the rules what disqualify GTs from becoming more than a curiosity in the rally world.