Don't know if anyone remembers Southern Airways, which merged to form Republic Airlines in 1979 and later merged with Northwest. Southern was an all-coach airline, but of course they branded themselves as the airline where no one was second class.

You might want to watch the three commercials that are on the page I've linked here.

All three commercials address the "envy" and belittlement factor of having a first class cabin. And all three suggest that the extra legroom in the first class cabin is created by taking legroom away from the coach seats. These are identical to the claims Elliott makes.

Personally, I remember flying Southern and liking them just fine. But I don't remember the coach product being superior to other airlines, and don't remember the seat pitch being greater just because there wasn't a first class.