> Can you share your thoughts on the downward pressure the miners put on the price of a bitcoin because they have to sell their rewards to pay for electricity?

There's not a lot to say you haven't already said. Mining is literally an increase of the money supply that devaluates each unit of that money, in this case. If the price remains the same, that must mean that its offset by an equal increase in demand. And indeed if the public interest stagnates, that offset won't happen and bitcoins will devaluate, you're absolutely right about that. But I'm not sure if there's some interesting 'snowball' effect going on here. Generally people withdraw their money from any investment that does not grow and has stagnated because there's no ROI there, so even if there was no bitcoin block rewards it's likely that if public demand for bitcoin stagnated to nothing that it'd still lead to people saying there's no ROI in bitcoin for me and as public interest has waned the utility of bitcoin won't grow either so I'm selling off my holdings. Such a mass sell-off would cause the price to fall, too. It's no different from say if there were 5 million people on Facebook and all of them only had 3-4 friends on there and public interest stagnated, people would leave and the value of FB would drop. Bitcoin block rewards aren't really a necessary aspect of that failure scenario, it can fail without it. If bitcoin can't beat inflation (which is at 9% per year), i.e. bitcoin isn't growing by 9% a year or so in adoption, then it's dead in the water regardless of inflation because that means that say assuming there are 5 million bitcoin users in the world, that in 10 years there'll be only 12m, and that's just nothing, imagine Facebook took 10 years to grow from 5m to 12m users, it'd have long been acquired by some other company or shut down and would have made no waves whatsoever. So bitcoin mining or not, if public interest stagnates for long enough, bitcoin's dead.

When I say 'dead' I mean as in 'insignificant because it's so small even if it's still alive', dead like myspace or something like that. If the price drops, miners will leave, but that makes mining for others easier. So it reaches a new equilibrium where the incentives to secure the system are lower, but the rewards to cheat the system are, too. Security doesn't really change much in bitcoin as it just finds a new equilibrium and as the incentives for security and anti-security move in the same direction. So it could still be secure, but if public interest stagnates and there's no adoption, no investment, no companies looking to build products and services etc etc, then it's insignificant anyway and will continue to decline until its fully usurped by alternatives.

An interesting idea is that inflation is set to halve in about 10 months from about 9% today to 4.2% or so. Assuming that new demand (due to companies like Coinbase continuing to grow) remains the same, while inflation halves, then we might see price increases again. And bitcoin sort of revolves around those, every time the price is set to increase you get this obvious flock of people investing short-term, a bubble emerging and that's when its in the headlines, when the message boards are flooded, when VCs invest more money etc. Without those bubbles bitcoin would probably have faded into obscurity by now. A lot of that block reward halving already priced in, in theory, but it'll be fun to see how it plays out this time around. Anyway so to answer your question, I don't think bitcoin has to worry about security if growth stagnates long enough, it'd be a bit similar to worrying about whether typewriters are ergonomic enough in a world where its completely irrelevant. Bitcoin has to grow, if it doesn't then its dead and its security isn't very important (although as I mentioned earlier, it'd just settle at a new level. Security incentives sort of self-adjusts to the value it has to secure).