There's a lot of people who keep saying "okay but how much are these users going to power up/ how many of them are going to keep their rewards/ etc", that doesn't matter that much in my opinion. If you believe Hive and all its advantages it gives users will grow, it's going to be their loss if they never held anything and looked to sell everything they could that they earned. Hive's inflation is quite limited and is decreasing in amounts yearly, don't focus too much on that. Sure it means that distribution isn't as good as it could be but I'm sure we could focus more on that in different ways than judging people only by if they keep or don't keep their earnings.
To reinforce your point: I recently did some Granger Causality analysis on how Powering Up and Powering Down impacts the price.
Basically, power downs have 0 predictive power when it comes to price, unlike pretty much every other metric I've analyzed. It's the weakest relationship I've analyzed so far. There are some potential outs, it's possible the impact of power downs is so spread out over time that it doesn't show up in this analysis, but realistically if there is 0 statistical evidence that power downs have a meaningful impact on price, people worrying about users powering down their Hive and selling it are probably focussing on the wrong issue. Most likely, the downstream effects of continuing to be active, producing content and contributing to the network effect, and even the fact that their potential curation rewards get redistributed to those users who stay powered up, outweigh or just neutralize the negatives of users powering down.