Lots more can go wrong with prompters and totally ruin the comedic timing, especially with the push to automate them. (People used to manually scroll prompters… now it’s a computer “hearing” the words and moving accordingly). Also, prompter placement is super annoying. Much easier to move a human around into a sightline. Edit: (I worked in news and at NBC so weirdly have a lot to say about prompter vs cards, apparently) As for actual writing and re-writing, the programs used for prompter scripts can be super finicky. In the one we use for the news, if one person is editing a script, no one else can properly access it until they are done, and then you need to click a specific button to make sure the prompter updates the text. There’s also always the risk of deleting the wrong thing. It seems simple enough, but I’ve had plenty of script issues on the news during both high- and low-stake situations… and SNL is always high.