> You can do it, it just takes $185,000 per application [...] and a super involved process.
And when you say “super involved”, keep in mind that part of the required process is to travel back in time to before April 2012, because “The application window for the first application round closed in April 2012. Comprehensive reviews of the program are currently underway to assess its performance in meeting intended objectives. These reviews will inform ongoing discussions with the ICANN community to determine when a second round will take place.” [0]
> Anyone can apply for their own TLD but it's not cheap. £130K+ a year iirc after a long application process
Anyone could during the one-time “new gTLD” scramble, but applications closed for that years ago; no decision on any subsequent round has yet been made, because the review of that first round has not yet been completed.
So, other than establishing a new country and getting a new ccTLD, there's no way to get a new TLD right now.
CERN is one of the rare cases this makes sense, since it's otherwise an international organisation with a domain under a ccTLD of a specific country (Switzerland).
It might make sense by the logic of domain names, but it doesn't by the logic of return on the investment of scarce resources. cern.org or cern.ch or cern.anything would meet all functional needs just as well and for much less.
Edit: s/can/could (thanks to child commenter).