What's wild is that the mirrors used in the EUV machines are smooth to a level of deviation even smaller that the feature size of the gates being etched.

These mirrors are up to a couple of feet in diameter, with an average smoothness deviation of less than the width of an atom, maximum bump size of 1nm or less. They like to point out that if scaled up to the size of Germany (Zeiss makes them), the biggest surface defect would still only be 0.1mm!