This is not technically correct, only practically correct. Hashing does not irreversibly become more difficult as a function of time, it becomes more or less di

This is not technically correct, only practically correct. Hashing does not irreversibly become more difficult as a function of time, it becomes more or less difficult as a function of total network hashrate. Now, there has been a strong positive correlation between time and total network hashrate, so for all practical purposes, difficulty has (and likely will continue to) increase over time. That said, if half of all miners went offline overnight, block times would approximately double, and the next difficulty rebalabce would go dramatically lower in an effort to maintain 20 minute block times.