I believe his intent, especially with the word "purportedly", was so infer that the proposed system had amazing abilities, less than it was intended to be a perfectly accurate description.
https://en.wikipedia.org/wiki/Diffraction-limited_system#/me...
I would guess that you'd need 0.25mm resolution, which at 200km would require 250microarcseconds angular res, which doesn't even register on that graph at any wavelength or size of telescope lol
edit: this is a very 'spherical cow' analysis. i'm pretty sure that atmospheric effects will kill your ability to image stuff like this well before angular resolution will.
Also, perhaps there's a need for a better naming system than one that produces ‘Extremely Large Telescope’.
https://en.m.wikipedia.org/wiki/Overwhelmingly_Large_Telesco...