Mining crypto currency is a hobby (or an income stream, or a business, depending on your level of involvement) that very much depends upon the prevailing market pricing of Bitcoin and others.
Reasonably enough, if the price of Bitcoin continues to free fall downwards (dragging the rest of the crypto currency market with it on the way), there will come a time when mining coins costs more than is offset by any possible profit made by selling or trading them.
Even if you are mining with a view to simply holding onto coins for an extended period - trusting that the market will rise again over time - it's hard to do at these current prices in the face of ongoing electricity and other hardware costs.
So, are we there yet? Personally, no.
Bitcoin, at the time of writing, is floundering around $5,500 - $6,200 (still a large sum for what some would say is essentially "nothing"). Counting in my electricity costs of around $0.14/KWh, I still come out ahead at the end of each month by a few tens of dollars.
As it's a hobby for me, and my hardware is essentially paid off already, then I will keep chugging along until the balance tips into the red. At that point, I will probably shut 'em down, at least for a time.
I don't see the blockchain technology "going away", and I think there is a lot of value to it. I'm just not sure if Bitcoin or other crypto currencies will end up being a true reflection of that value.