Have you tried getting a good, unused name today? Anything remotely close to a dictionary word, if unused, is squatted with a $xx,000 price tag. Do registrars get a cut of these sales prices because it seems ridiculous to allow squatting.
Neither registrars nor tld operators care about squatting, even when they don't get a cut. Why would they? The squatter is paying them the same as you'd pay them.
But at some point we will also exhaust all nice TLDs too...
It will be even more difficult than it is now
What positive outcome comes from squatters sitting on unused domains?