I'm self-taught on guitar.
As a teen I'd sit in my sisters room and wear out her vinyl LPs.
I'd life and lower the needle again and again, listening to 2 to 4 second segments to figure out by hear what chords they were playing.
Developing a good ear is rare today, since all chords of all songs can be found in seconds, no work, no skill needed.
I did that with Crosby, CSN, CSNY, Dylan, Donovan, Baez, John Denver, Elton John, etc.