I think you are probably right about the monitor feed. For color TV in general, I must have just been lucky to have always had one except when I was less than 7 years old. But even still, looking back, there are other oddities about television shows, like the voices of some characters seeming to change from what I remember. My grandparents getting a color TV when I was about 7, which would have been in about 1964.
I don't remember any B&W cartoons, B&W Disney shows, B&W Star Trek episodes ( except the pilot which I saw years later ) or anything else except old reruns of Gomer Pyle or Andy Griffith in B&W. I also remember the pictures being really clear, not like the blurry stuff we often see on Youtube. But then there are the exceptions, so it's likely just timing and a combination of other mostly explainable factors.
Now back to our regular programming ...
Any Yet Another Version Of The Classic - Tubular Bells
Tubular Bells, now there is a record I have not thrown on the player in a few years.