Can you give me a citation on the "10% of the milder COVID cases still are not recovered after 6 months"? I haven't found any good studies on this, and the "milder" in your sentence implies that you not only found research, but you found research that breaks it down by infection severity.

My google fu is failing me when I search for it though, so I would very much appreciate a link.

I read it in the news here https://www.tagesschau.de/inland/gesellschaft/longcovid-101.... (German unfortunately and no link to the original research...)

"Epidemiologische Studien zeigen, dass etwa zehn Prozent der ambulanten Patienten nach sechs Monaten unter Long Covid leiden. Von diesen Patienten sind wiederum zehn Prozent vom chronischen Fatigue-Syndrom betroffen, schätzen Wissenschaftler. "

At least the cited scientist is easy to Google, so you could ask her directly for the studies: https://solvecfs.org/carmen-scheibenbogen/