Okay, I'm just going to come right out and ask the question: why are some people out there obsessed with this kind of thing?
I have to admit, as a 4 year old to late teens they were scary to look at, and reminded me of government propaganda since they filled the entire screen. When I was younger kid (maybe 2nd grade, before youtube), I went to an indoor camp and some kid (probably with autism) recited the fundings word for word. Right before I first found these on youtube, I would secretly check out PBS documentaries from my local library just to see what they looked like, and I learned "Viewers Like You" was their slang for "PBS" due to the covers (I found it confirmed on PBS' website years later) saying PBS instead of Public Television Stations and Public Television Viewers. Enter YouTube and the fanbase skyrocketed after a user named Synstyte78 (spelling) first uploaded the Reading Rainbow funding credits, and the closing logo group talking about scary logos like the 1971 PBS logo. Take that with young "PBS Kids" viewers and tried to make fake funding credits, whether the show existed or not.
Before the internet, there were some jokes about fundings, like in "The Simpsons" episode Missionary Impossible. (allthough the internet existed in that case). But these were done by regular adults and politicians who watched PBS regularly or helped CPB get your tax dollars.
And that, my friend, is how this fanbase grew........but even after all these years, I'm not the biggest fan of them, kids will learn more about bueraciarcies than actual education.