Goodson always kept copies of all of his shows. He wasn't a visionary who could possibly have foreseen cable TV or any rerun value for his shows. Maybe he took a cue from Desi Arnaz and kept them anyway.
ABC "Password" and syndicated "Concentration" don't seem to exist, except for the few episodes floating around.
Also, while a considerable number of NBC nighttime (and one daytime) episodes of Cullen TPIR (kinescopes, right?) exist, only three or four ABC ones do, for whatever reason.
On the other hand, do any 1960s daytime CBS
Passwords exist, other than the last season that had cuts made so they could be syndicated? How about CBS daytime
To Tell The Truth, other than the last episode? Then again, both of those could have suffered a different problem; color video tapes from that era tend to degrade much more quickly than later ones.
Has the possibility been considered that some of the shows still do exist, but no one particularly wants to pay to convert them to something that can be aired now? (Do we need to have every episode of Trebek's Double Dare? Or any of Mindreaders?)
Given that most CBS
Double Dare episodes have aired, I assume the tapes didn't need converting.