The Majorana particles in Microsoft's set-up are "quasi-particles". They aren't really fundamental particles, but excitations in the system which behave (roughly, in some appropriate sense) like particles. They aren't neutrinos.

Quite confusing though

> “There’s no slam dunk to know immediately from the experiment” that the qubits are made of topological states, says Simon. (A claim of having created Majorana states made by a Microsoft-funded team based in Delft, The Netherlands, was retracted in 2021.) The ultimate proof will come if the devices perform as expected once they are scaled up, he adds.

https://www.nature.com/articles/d41586-025-00527-z