This is rather silly. Third level domains aren't particularly unique or hard to do. It likely costs about nothing to just deprecate new registrations and keep the existing ones around. If I had to guess, they're wanting to auction off the second level domains which will likely bring in more money than the rather unpopular third level registrations.
Yeah, I'm looking forward to being priced out of the domain I've been using for my email for 13 years now. Fun times.