Yes and yes.
I used Box Office Mojo to look at the top 10 grossing movies in the U.S. from 1980 through today. I could have gone further back, but I'd consider the post-Jaws and Star Wars era to be the start of the modern era of blockbusters, so this seemed like a good place to start.
I did my best, but you may look at a couple of these years and disagree on a few movies here and there. Here's a couple examples to show how I counted things:
- 2022's The Batman is not a sequel, but it is a super hero movie. I could see why someone would consider this a sequel, but I didn't count reboots as sequels.
- While Black Panther takes place in the MCU, I did not consider it a sequel, but of course it is a super hero movie.
- Remakes are not sequels. So Doctor Dolittle and live action Disney movies did not count as for me.
- Movies based on preexisting properties are not sequels. The original Transformers was based on a cartoon and toys, but it wasn't a sequel.
- Prequels are sequels (Star Wars Episode 1) unless they're a total reboot (Batman Begins).
You could disagree with some of these, but honestly they would only shift some years by one or two points max, so the graph would have the same trends.
- 2011 had the most (8) sequels in the top 10, with the only "original films" being two super hero Marvel flicks.
- 1998 had zero sequels or super hero movies in the top 10. Godzilla and Doctor Dolittle were based on older films, but that's as close as we got.
- 2020 won't be remembered as the best year of film, but the pandemic did cause studio to hold their big budget (mostly super hero) films, which meant it was a more original, less hero-y year than anything since the early 2000s.