Come on, smth can be or not be delusional only dependent on its intrinsic tech and people backing it up. In case of BTC we've seen it being operable and with enough supporters of all ranks. In case of other projects, say Ethereum or Lisk, there's a whole army of top tier devs and people from business to solve problems arising in front of it.
If your point is that BTC can be partially decentralized via mining pulls and stuff, I'll allow myself to direct your attention to V. Buterin's words on what can be named decentralized ("The Meaning of Decentralization" on Medium). People understand it quite differently, it turns out.