Of COURSE the f-ratio is related to the aperture, but did you read down as far as "Mathematical formulation", where you conveniently missed out:
The radius q1 of the first dark ring on a screen is related to theta and to the f-number by q1 = 1.22 lambda N (where N is the f-number)
(End quote). This is a commonly quoted formula involved in calculating the spot size. For the mathematically challenged, at the same wavelength of light, the Airy disk size increases linearly with f-ratio.
In practice, I agree, a small scope will be diffraction limited, but a larger one is less likely to be, especially along the east coast of Australia. I think we're essentially saying the same thing but just not seeing it that way
And FWIW, your condescending tone is not appreciated. This used to be a friendly forum and I might suggest you pull your head in.