The Thanksgiving and Christmas specials aired every year, and might still. But who has an antenna any more? I do.

The combination of cable-cutting and the fact that many people either can't access OTA (or don't bother) probably means that a lot of the content that people reflexively tuned into over various holidays just doesn't happen any longer. Even if some of it is on streaming, it's not an automatic holiday thing.

I can't get OTA and cut cable TV so I don't get a lot of things without effort that I don't generally go to.

Apple bought the rights years ago, PBS cannot show them anymore, they are now behind a paywall.