I think some slide notes could be created even if it takes some extra time. Some viewers might be there to learn and wants some notes/references while others are there for entertainment. If everyone is forced to take their own notes it might take attention away from the presentation itself.
I find that notes are a natural result of preparing a talk. I write the notes to work out what I plan to say while designing the slides to support the script. The notes are the main way to communicate with people who weren't there or who need a reminder of what was said or to follow up references.
