The Tonight Show epis I'd dearly like to see (NBC recorded over them...), or at least listen to, are the ones of Bill Dana's "Jose Jimenez" appearances during the Apollo 11 mission.
There were also people home taping audio from television and radio.
I did it myself in the 1970s and 80s (no VCR).
I saw one time someone who had a trading/selling list of around 10,000 hours of programming (maybe in one of the record collecting or movie paper collection newspapers). What I recall seeing on that list was pretty amazing (I never got the full list nor did I ever try to get any recordings from him).
Professional sports frown on home recording/sharing of their events.