99,9% of people in world dont know wtf that 3 things are! Only corporates are interested in that features and corporates arent interested in bitcoin...
And also, you can multisig in fiat currency; you can do smart contracts too.
The immutable ledger can be a disadvantage too! You cant null one mistake or a swindle.
you have to read more about it and find out. you are already here, good first step

i end with a quote:
"If you dont believe me or dont get it, I dont have time to try to convince you, sorry."Yeah, uh, that's bullshit and errornone is right. Immutability is far more often a flaw than a feature, multi-party control of escrow/whatever for fiat exists, and 'smart contracts' have only existed in the fiat world for decades