Factually wrong information a lot of people seem to believe? (Spoilers Main)

I have come across so many people on this very sub saying that Varys adviced Aerys to open the gates to Tywin....when it's clearly stated that he adviced against it and that he played a role in the extinction of house Darklyn or the defiance of duskendale by whispering weird things in Aerys' ears when he came to king's landing after those events from what I know

In general, the fanon about Varys seems to have superseded the canon although that probably has a lot to do with him being such a mysterious character

Are there any other widely believed misconceptions or fanons?