I think your picture is slightly inaccurate. It is more like, there are the random arxiv pre-prints, then 1 in 1000 of those get featured in popular press like

I think your picture is slightly inaccurate. It is more like, there are the random arxiv pre-prints, then 1 in 1000 of those get featured in popular press like this or are otherwise truly remarkable, and 1 in 100 of those make it into the textbooks. The Gauss and Euler results you find in textbooks are not mundane, they are the "arxiv pre-prints" of 200 years ago that made it through the filter of time because they turned out to be important or deep.