> I'm pretty sure Liberland's case classifies as “no man’s land” (neither of the bordering countries wanted it, and nobody else bothered with it, too). Still, once Liberland established a country there, suddenly everybody wants it.

The reason “nobody wants it” is that it’s similar to the Bir Tawil triangle: accepting it as part of your country means abandoning your claim on the larger and more valuable area linked to it in dispute.

It does not mean a third party gets to come in and go “well if nobody wants it…” it’s still part of the contention.