Sony already confirmed RDNA 2. I don't understand where this confusion is coming from (I heard it on the PC Perspective podcast too).
Too many folks are reading and following certain console conspiracy theorists, and it seems to be spreading into the technotubers as they will cover anything for video hits.
Their next report from their sources ... "Every new PS4 game you buy this holiday will work on PS5 when it arrives in 2021"