I'm not saying bag holding is a good or a bad thing, but I think people sometimes don't realize how high BTC is going to have to climb to beat the other investments you can do in this space. Based on my last years average return of 0.1026% on USD margin, lets look at some numbers:
That return is unsustainable unless Bitcoin keeps going up, and in that case, lending USD wouldn't be that profitable in comparison to lending BTC.
What makes you think that? That average is over the last year since ~January 15th, a period in which the majority of the time we were going down, not up. The problem isn't BTC going down or up, but going somewhere. When prices move, USD gets lent out. When prices sit still, USD lends sit still...