Old characters refered to as "new"

I was wondering why do some old characters that I remember from when i was a kid, such as Telly and Elmo, get treated as if they are brand spanking new.
Did people just forget that they were around in the mid to late 80s? (the period when I watched)

No, it's just that "people" were around in the mid to late 70s.

When I was starting to outgrow the target audience (I was born in 1980), Telly was firmly established, but Elmo was just starting his rise to power.

I think Kevin Clash's casting as Elmo is probably the dividing line between "old" and "new" characters.