I call BS, and am wondering if he has indeed taken Route 66, or just telling some vague impression he has of what it would be to do so.
I've travelled Route 66 several times (and highway 1, Highway 61 -Louisiana to Canada-, Route 50, coast-to-coast several times, and several other long road trips for decades).
There's nothing "touristy" about Route 66, with the exception of a few small towns along the way with shops living off of the Route 66 travellers.
Considering the whole 2.500+ miles journey, those are a negligible part of the way. And even those few places are not touristy in the Las Vegas or Miami sense, but more of a decadent, quiet "that's what we've got from our past, and we preserve it and tout it to help make some bucks" sense.
And there's nothing (unlike on a train) that stops you from talking small roads and alternate routes to explore nearby smalltowns and counties.