OK, so every 8 zeros represents 4294967296 (almost 4.3 billion) times faster bitcoin hash rate.
So we got more than 5 more sets of 8 zeros, or 4.29 billion x 4.29 billion x 4.29 billion x 4.29 billion x 4.29 billion
Which is an exponential increase, not a linear increase ... it wont happen.

Edit: reminder that 2^256 is close to the number of atoms in the universe (only about 1000 times smaller)