I don't think more depth would have been appropriate to the intentions of the producers. After all, I guess the target audience is not the scientifically literate minority, but rather the remaining majority of viewers. I suspect the series was a great success, just as Carl Sagan's was. An inspiration. Those who are confident that they already know all that stuff, and want to learn more, have access wealth of relevant videos on YouTube.

"Time is what prevents everything from happening at once" - John Wheeler