Videotape was really expensive in the early years of TV.
The network headquarters I worked at wiped out tons of 60s and early 70s original programming due to the price of tape.
I copied a lot of quad tapes to digital Beta.
Some disintegrated as they played back.
I managed to snag one for myself as when the tape vault was being purged.
Thousands of tapes in all analog formats were tossed.
IIRC that’s what happened to the first decade or so of the Johnny Carson show. The tapes got wiped and now those episodes exist only in people’s memories.