Prior to the Peanuts specials, television animation was seen as being cheap and disposable. Walt Disney wouldn’t even touch it and what did air was mostly repackaged theatrical cartoons. Charles Shultz didn’t want to make cheap specials that wouldn’t be remembered thirty minutes after they aired. He was looking to create something special that would outlive him. While Coca-Cola and Dolly Madison were most likely delighted that the special would have legs, they probably hadn’t expected that the specials would still be watched and enjoyed 50 years later.
Much of the credit for that goes to the team that was assembled to produce the show. Bill Melendez, who produced the animation and Vince Guaraldi who produced the score had the same high standards that Charles Schulz championed. They wouldn’t talk down to kids or assume that quality didn’t matter because the specials were “just for kids”.
It was this attention to detail and quality that made these specials live long past the expiration date of other less ambitious productions from the same time period.