According to Bitcoin Core developer Luke Dashjr, a miner’s main motivation should not be profit, but the desire to keep the network secure. This discussion began when Luke tweeted that people are abusing SegWit‘s block increase to take advantage of legitimate Bitcoin users. Luke also took the opportunity to state his opinion by saying that the size of the block should be reduced rather than increased, as many claims. The community even took the opportunity to pin Luke saying that his view is opposite to that written by Satoshi Nakamoto in the Bitcoin whitepaper.
In theory, Luke may be correct, miners have their degree of influence on the Bitcoin network, if they were driven by a passion for keeping the network safe, their decisions would not be selfish, see Segwit2x.
However, we can never disregard that the market is free, and Bitcoin is decentralized. The current mining situation was an adaptation of the free market and is therefore not illegitimate. Bitcoin’s gigantic hashrate is a consequence of the rapidly advancing free market in the creation of mining-specific machines. But for Luke, this advance brought Bitcoin the centralization of mining and nodes, and to solve these supposed problems, the solution would be to shrink the block size and change the Proof of Work algorithm.
Some protocols have been architected by default to not reward transaction validators, for example, Nano’s Open Representative Voting (OPV). In it, people who run a node and help validate transactions do so because they believe in the project and not for profit. Each representative in the network has a weight, which is determined by the amount of coins he has delegated. Currently, running a node on Nano’s network is cheap, but surely that cost would increase as adoption increased, so as Nano adoption is not close to Bitcoin, we can’t believe 100% viability of this model for now. We believe that only time can give us the answer. At this point, we can follow beta testing and protocol evolution.
