Yes, F students are the inventors
And there's one other thing inversely created with creativity: the other type of grade.
Later grades tend to have more grindy classes
I analyzed the schools I went to as a student. In 1st-4th grade, there was an air of creation and thinking - making art or writing was common and for all students. In 5th grade, it started fading away. The main creative project I remember was building a physical bridge. But there was plenty of time to make your own things and consume other people's.
Middle school asymptoted. Electives were dedicated to creating performances, robots, virtual objects, and physical objects, but only were part of the day. Other classes occasionally assigned writing or slideshows, but only occasionally.
High school lost most creativity. To be fair, some stayed the same, like English and art (consistent high level of creativity) and math (consistent high level of open ended problem solving). But history went from occasional worksheets to daily worksheets, and from earnest presentations to rare essays. And science went from one of the most engaging classes with numerous opportunities to create knowledge and content to a worse version of Khan Academy.
More advanced classes also tend to be more grindy
The most advanced classes tend to be AP classes, which are defined by the presence of a test. But this test isn't on trying to figure things out from first principles or solving novel problems, so most teachers end up teaching these classes in the most boring way possible. They do the bare minimum to say "I taught the AP curriculum". They feel like... well, look up at the cover image of this post.
And this spawns grindy students
[Coming soon: real data]