no real consequence for powering down = no real consequence for selling into new lows.
power-down should result in decreased voting power and/or decreased interest gained on SP
otherwise, the system is an inefficient engine, leaking power into the atmosphere
The power down does result in decreased voting power because your vests reduce each time you power down. The only way to increase the vests back to what they were is to earn steempower through writing or curating or both.
But its not a tangible consequence, plus the amount you lose each week is barely noticeable in terms of voting power decreases. Also, despite the power downs, the SP gained per second continues ticking away, so amount lost is even more negligible.