That reminds me about one other use for the slides editor like power points and google slides: creating posters. It's much easier and faster for an inexperienced person to create a poster from scratch (for your paper, conference talks, etc) with those slides editor than using vector graphic editor like inkscape or coreldraw.

It's probably already obvious for people who regularly uses google slides / keynote / powerpoint, but for me who very rarely use them (but often use various graphic editors) it's quite a revelation.