I think about it in terms of the long game but I also don't lose my mind and invest foolishly.
Like most sensible people I don't keep Steem/SP as my only investment and neither should anyone else. I believe in the future of this platform but I'm not stupid and neither are the whales or the founders.
Those who are powering down are probably doing it out of necessity as you state in your post. These people are buying services, hiring people and expanding the platform to help create a future for Steemit.
The knock on effect of this is greater liquidity on the market making it a lot cheaper for minnows like myself who strongly believe in this platform to steadily power up.
I have been doing this for the last few weeks and have gradually added nearly 2000SP to my account - bringing me close to the milestone of 4000!
I will continue doing this but I understand I am in kind of a privileged position as my other investments in crypto allow that.
For those that aren't actual founders or whales (as they will already know this) I would suggest that you always diversify your crypto holdings. There are no certainties of success here. The DAO/ether fiasco is just the most recent example of that.
Anyway since I have that "cushion" of protection I will keep powering up as much as I can and supporting this project in my way.
^^^Words of wisdom!