Talking Point: David Mitchell gets grumpy about kids' TV, but does he have a point?

I'm sure many of you watch David Mitchell's Soapbox, a series of vodcasts where the writer-actor most famous for Peep Show aims his intellectual cynicism at various topics. In the latest edition (embedded above), Mitchell targeted children's TV, and his disbelief that many of today's adults watch it. He throws particular scorn on the fact adults are encouraged to watch Doctor Who, and argues that grownups in the 1920s weren't reading books like Winnie The Pooh unless they had kids. They certainly didn't require a specialist Harry Potter-esque "adult cover" to mask their guilt in the bookshop.

Does David Mitchell have a point? Is children's entertainment frequently marketed at adults, just to boost sales? Have today's adults simply failed to "grow up", infantalized by the modern culture? Or has David Mitchell simply got it all wrong, and the examples he cites (Doctor Who, Harry Potter) are "family entertainment" with a broader appeal (unlike Winnie The Pooh)?