Information-heavy slides have their place when you're also handing paper printouts to everyone present - otherwise knowledge transfer to any individual gets limited by both their working memory and by how sharp their vision is vs. how far are they for the screen. This is really bad in school setting in particular, as kids may not even realize they find the slides boring just because they're sitting too far back.
The information heavy slides are usually the handout.
I have also seen McKinsey style slides be information heavy, work fine on screenshares.
It's important to remember a stereotype of presentations is sparsely focused pitch decks needing to be the only format for everything. I like this format a lot, but would be missing certain opportunities where it comes up incredibly short, because people don't remember 50% twenty minutes later.