This seems quite a bold claim that Microsoft proofed that Neutrinos are Majorana particles...
Huh? This has nothing to do with neutrinos.
The chip is literally called Microsoft Majorana 1
Indeed Majorana fermions are completely unseen/unconsidered outside of Neutrinos. In fact all Standard Model fermions except Neutrinos are proven to be Dirac fermions
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 (A claim of having created Majorana states made by a Microsoft-funded team based in Delft, The Netherlands, was retracted in 2021.)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.
I'm not sure what that has to do with my previous comment but yeah, pushing the boundaries of science is kinda difficult and you can make mistakes.
My understanding is that they pretty convincingly showed that the thing they built acts as a qubit. This means that if its not doing what they think its doing (the "topological" / Majorana stuff) then they accidentally made a qubit which works some other way. That isn't outside the realm of possibility but it is fairly unlikely.
You are confusing quasiparticles with fundamental particles. If we were to observe a Majorana topological state, this would have no bearing on the properties of the neutrino.
Also to say Majorana fermions are not considered outside of neutrinos is a patently ridiculous and ignorant statement. There is absolutely nothing in physics to say the only particle that can possibly be Majorana is a neutrino. For example, there have been theories of Majorana dark matter which are a consideration of fundamental Majorana particles outside of neutrinos.