Sesame Street season one. Not suitable for children.

[enlightenment]

30. My kid was born in 1980

and loved Sesame Street and that other show (Fargle something . . .) - he also loved Wild Kingdom (I had a tougher time than he did with the "this is life on the Savannah" moments, as the lion brought down the baby gazelle) and some of the other nature shows. That's all he was allowed to watch and he never watched any program unsupervised (in other words, I watched them along with him).

Those shows never had an impact on his attention span, which was unbelievably long when he was engaged with something and typically short when he wasn't. I don't think you can lay the blame on Sesame Street - I think it's more the environment in which the products are consumed. If you use a TV as a baby-sitter, it doesn't matter if the show is something as inane as Barney the Dinosaur or as deep as Ted Talks - your kid is not interacting with a human, but with a machine (same goes for all these "educational" toys and videos). That is going to impact their ability to cope with the real world. Full stop.

Turn off the tube, replace the button pushing gizmos with building blocks, butcher paper, crayons, and books - and spend time with your child while they're learning what it is to be human. By the time they're ready to start school they may actually be ready to be interactive, functioning members of their little society.