He does seem to eliminate beforehand any writer whose works are largely pre-1926. I would put ERB in the "honorable mention" category, his books are still quite readable & enjoyable today.
I’m just finishing up the Barsoom series again. His books are flawed but seriously enjoyable.
When John Carter first arrived on mars, he stated as fact that there are no birds on Mars but by the time you get to The synthetic men of mars he has them riding giant birds.
On the other hand, much of what he imagined has come to pass in some manner or another. He wrote that mars was a dying planet before we had a clue, he imagined cloning etc.
If you like lots of technical Details, Robert L Forward was good because he was a physicist. His company “Tethers unlimited” was introduced in Saturn Rukh an exists as an actual company today with many earth and space bound applications.