Prices for short domains are mostly driven by global domainer demand vs. lack of supply. gTLDs are priced low enough that domainers can reg them all. With none available to reg, anyone who wants a short domain has to pay whatever the market wants.
I don't see this happening in all ccTLDs simply because many of them are too expensive. Plus for the most part the demand isn't there. Case in point: amazing.com would probably be worth more than g9.com. So if Amazing.ac is available, why would a domainer reg g9.ac?