Ah gotcha, I didn't realize they were different shows. Did a little more digging, and here's the warning on Sesame Street: "These early Sesame Street episodes are intended for grownups and may not suit the needs of today's preschool child"
It sounds like it's about things that are no longer considered safe for kids, compared to the 60s:
>"We wouldn't have children on the set riding without a bicycle helmet," Rollins Westin says.
> And what's that little girl doing with that man?
> "In the very first episode, Gordon takes a little girl's hand who he's just met on the street, befriends her and takes her into his home to give her ice cream," Rollins Westin said. "That's something we wouldn't do on the show today."