I personally think he is being very impractical. Only a minority of people really understand science and rational thinking to make that their primary spiritual realm.
I think you are too pessimistic about people. When I read my first pop science book last year I found it very difficult to follow (a briefer history of time), however the more I read and listen to pop science the easier the information has become to understand.
I didn't find his talk that complicated - even if it was my first introduction to pop science, I'm sure that I could have followed it. The TV series Cosmos by Carl Sagan isn't difficult to follow, even for those unfamiliar - and that is really the level of pop science knowledge that is required IMO to use it for a spiritual narrative.