Significance
The finest detail any telescope, microscope or eye can resolve is set by wavelength over aperture — diffraction, not workmanship, is the floor. The 1.22 is the first dark ring of the Airy pattern that a circular aperture makes; a slit or a square would carry a different constant. It is why telescopes are big, why radio dishes are enormous and then combined into interferometers to fake a bigger one, and why no visible-light microscope will ever show an atom. It is also why JWST is not sharper than Hubble: working at 2 μm instead of 500 nm costs a factor of four, and 6.5 m of mirror against 2.4 m buys back less than three, so JWST resolves about 0.08″ where Hubble manages 0.05″ and would need a 9.6 m mirror to match it. What the infrared buys is not sharpness — it is seeing through dust, and seeing light so redshifted that Hubble cannot see it at all.