Also have been hearing this not too seldom. Notice that, again, this is not a newbie member:
If bitcoin was worth 2 dollars a coin it will quickly cease to exist. At 2 dollars a coin it is not only NOT rpofitable to mine, it is actually going to cost people money to mine. Bitcoin needs miners to process transactions, without miners the blockchain freezes and no confirmations are made on your transactions, So at 2 dollars a BTC no one would want to mine much less be able to afford to mine.
Just a blatant misunderstanding of the mechanism of difficulty re-targeting.

Protracted bear market declines test even the finest minds, sending impoverished newbies into the dark world of trollery, senior members feel the icy fingers of doubt intrude and the Heroes continue unabashed spouting faintly encouraging burblings and whimsy.