There are optical telescopes that use interferometry https://en.wikipedia.org/wiki/Astronomical_optical_interferometry https://en.wikipedia.org/wiki/Astronomic

There are optical telescopes that use interferometry https://en.wikipedia.org/wiki/Astronomical_optical_interferometry https://en.wikipedia.org/wiki/Astronomical_optical_interfero... But given the we don't have multi-THZ digital sampling, I guess, all the work has to be done in the analog domain in realtime... which is pretty limiting compared to what is possible with radio.