If Mining BTC Even with free electricity cannot pay the mining equipment in a year, that will be the doomsday of BTC, 2000$-2500$ is the limit.
Your seem to be clueless with your analysis, how were miners able to cope when bitcoin wasn't worth $1,000 ? and Bitcoin at it's worse of the year so far is worth more than $5,000. You need to understand that electricity carries a relatively huge percentage of mining cost.