For the week in question, The Tonight Show takes the crown. Dr. Jane Goodall was on the show on April 22 to help commemorate Earth Day. The Late Show comes in (a distant) second, with Bill Gates visiting virtually to discuss coronavirus testing and vaccine research with Stephen. Gates notably warned about pandemic preparedness in 2015, and his foundation does a lot of work on public health issues around the world.
Also of note that week was another appearance by “Science Bob” Pflugfelder on Live With Kelly and Ryan. His last appearance on the program wasn’t that long ago, but with newly minted homeschool teachers needing science content, it makes sense for Science Bob to step up.