We definitely need more market research in understanding the reasons for powering up and powering down among other things. This type of data is gold for every other social network out there, but nobody seems to care or have enough time to be bothered about it here. This is exactly the type of insight we need to stop stabbing in the dark and start informing our decisions for building a better platform.

AFAIK, the reward pool is based on a % of the inflation, and the inflation is determined by total supply. The inflation % changes year to year, steadily declining, but as the supply keeps rising, the effects of the percentages are compounding.

I do think there's a bigger cost to some flags than people realize, but without any regulation (flags), we've seen how much the reward pool gets abused. I think the community can find a balance if the right incentives are baked in, but it will be a bumpy ride there.