I get Elmo’s the very big popular one on the series with the appropriate age range group, but frankly it just feels like a big, unecesarry double standard (and kinda makes the workshop look like absolute fools in honesty) to just have this mentality that feels like “Yeah, sure, let’s just let the kids know these characters looked or sounded different back in the day. The parents will be with them. But this furry little red guy on the other hand? NOPE NOPE NOPE NOPE NOPE, that never existed! LALALALALALALALALALA! *fingers in ears*” okay, bit over exaggerated on that part, but that’s kind of how they also make themselves look with this mentality.
Plus, in fairness, I’m sure they’re also well aware that older audiences have been curious to see footage of Elmo with a different voice; they’re no doubt aware of fan uploads or articles on the muppet wiki, a place where many older fans I’m sure explore the wiki frequently, explaining his different performers, especially since one of the admins is good friends with the staff at the workshop.