1. I can't give exact definition of centralised and decentralised.
2. Number of malicious node and whether other node collude or not mostly doesn't matter since full node supposed to verify everything.
3. Even miner can perform certain attack which doesn't violate Bitcoin rule, such as selfish mining and intentionally exclude certain transaction.
1. If you can't give a definition how do you know that btc isn't centralised ? This reminds me the documentary "what is a woman"
https://twitter.com/Gidi_Traffic/status/16977476796593603222. In an environment where the majority of nodes are mallicious , -i think- you will verify a false ledger .
3. If that is valid , why don't we see selfish miners and other attacks happening everyday ? No one leaves more profitability on the table , especially in that sector . Maybe there are other reasons that make pools stay honest ?
1. That's because creating criteria and measuring decentralization isn't easy. Although i could just point to definition on dictionary such as these,
Adjective
decentralized
not centralized; having no center or several centers
Isn't it quite easy to define centralized and decentralized in technical terms?
Centralized - there is a central server that serves all of the nodes and computers who request data from it
Decentralized - each node and computer functions as its own server, and many other computers connect to each other to request for data as they would from a server.
Technically speaking, Bitcoin was centralized when it ran on only one computer (Satoshi's node/miner).
As soon as someone made a second node/miner it became decentralized.
Of course there are also other criteria.
For example, BSV has a mechanism to steal coins from "criminals" with a court order.
Does that make it decentralized (despite having many BSV nodes)? Not really.
ps: HmmMAA is a huge CSW/BSV fanboy.
He doesn't even mind Calvin Ayre's pedo shenanigans... go figure!