1. So remember that bitcoin has had its 51% event - in 2014, when GHash went over 51%, and promptly split into smaller pools, so as not to spook the suckers. No

1. So remember that bitcoin has had its 51% event - in 2014, when GHash went over 51%, and promptly split into smaller pools, so as not to spook the suckers. Nobody talks about that now. But from 2014 on, bitcoin mining was indisputably centralised - it's only ever been decentralised in the sense of "can't sue me bro", not in operational practice. In 2015, the men controlling 80% of bitcoin mining stood on stage together at a conference. Three or four entities have run bitcoin mining since then - assuming they don't share ownership behind the scenes. The only thing preventing miner misbehaviour is wanting to avoid spooking the suckers. That's the game theory here. The miners would love to increase the reward. The trouble will be selling it to the subculture. They'd need to make a convincing case that it was necessary to number going up. 2. You're correct: no money comes out of bitcoin that didn't go in. So for everyone who got rich, there's a pile of suckers who got poor. Everyone who talks about bitcoin as an great investment does so with massive survivorship bias. A securities issuance is supposed to (this is the brochure version) fund investment in a productive enterprise. You get a pile of capital together, you invest it in an enterprise, it generates wealth. A pile of bitcoins can't do that. It's just a pile of a commodity, that doesn't do anything else. All you can do is buy, hold or sell it. Early bitcoin buyers are only ever paid with actual dollars from later bitcoin buyers. This is technically not a Ponzi, because nobody is running it, but it works very like one. Holders are incentivised to promote the scheme so as to help grow the supply of later bitcoin buyers to offload their bags onto, so they can cash out at all.