No its not a generation thing, its Brits teeth in general. We used to defend it when we first moved over here but now when we see family, friends and even TV presenters is very apparent what Americans were referring to. Heck my parents were pretty well off by UK standards, we always had private health and dentistry growing up yet their teeth are substandard.
There are plenty of people over here with jacked up teeth but usually the very poor and redneck types. Its extremely rare to see middle class people with anything but perfect teeth. And the chances of getting on TV without perfect teeth are slim. I think cosmetic dentistry is a little over done State side but its practically none existent in the UK. You just wouldn't see anyone with Clarkson's resources with nasty jacked up teeth like that.