Any btc price prediction should be taken with a grain of salt.
Is it possible? Yes
Probable? Maybe, if this decline is structurally similar to $250 to $70 decline in the summer of 2013.
Bitmain and Innosilicon (competitor) are producing vast amounts of mining machines and people are buying (so far).
Right now when mining at a cost of 10c/kwh, breakeven point is somewhere at $7000-8000/btc.
How likely would be a five-fold difficulty increase in 1.5-2 years?
Quite likely as it would take slightly less than 4% increase in difficulty per adjustment period (about 13 days).
last five adjustment periods were 6.91% on average.
last 10 adjustment periods were 5.7% on average.
With 5.7% adjustment per 13 day period in the next 1.5 years, btc price would have to be $70000-80000/btc for miners to break even when mining at the end of that period (end of 2019, early 2020).
These are excellent points. I also did a similiar calculation a while ago and realized that btc was not profitable to mine while around 6k. I noticed very few people make an effort and do this kind of analysis. Like you said earlier, people are lost in their emotions instead of keeping a rational outlook or dig a little deeper to understand the costs of mining. Based on that the 60k projection appears suddenly not so outlandish any more.
I see the logic of extrapolating from current profitability, but I don't think it's correct, because it assumes constant bid-side demand.
It doesn't matter what it costs to
produce BTC; it only matters what the market is
willing to pay for it. If the market isn't willing to pay $60,000 or $80,000 on the above timeline, then difficulty will simply drop. Perhaps it will even plummet in a death spiral.
Miners aren't guaranteed profitability by any means. Marginal miners are constantly getting squeezed out of the market, and if there is a reversal in the general trend, there could be a blood bath of miners shutting down. This is all totally unpredictable.