It sounds plausible, I’m a bit stuck on the a holder is a holder no matter where they are self custody or third party,
I totally disagree with your opinion. It's not the same measures as FIAT money because if you want to save that money you need a bank account since you cannot store cash in a personal vault at home. In the other hands, bitcoin can be stored in an offline wallet encrypted with complex algorithms installed in our personal devices or even without an active wallet, you just need the private keys who can be stored in a writtable metal or even a small piece of paper.