IIUC he claims that most of them are just internal notes. In the research group I am, we generate a lot of crap. I'm not sure we reach one per day, but probably 3 per week, but we have some "productive" weeks from time to time.

Sometimes I just write an email (in text) but sometimes it's a short LaTeX document (3 pages, title, date, my name, may have an introduction to ensure we use the same notation, usually no references because I'm lazy). Some of my coworkers are using AI that likes to make longer stuff and format it like a letter to the Nobel foundation.

Some are good, most are wrong or bad. Some are reproductions of others research work, some are early experiments, some are rediscovering the wheel, some are misguided ideas, and lucky a tiny part are good. Anyway, they are for internal use, we don't try to contribute to the thermal death of the universe uploading that crap to a free preprint server.

I don't understand:

a) Why they upload internal notes/reports to a preprint server?

b) Why are these reported as "academic papers"?