No, Prius hasn't been upgraded to TSS 2.0 yet like some of the other cars. Posted via the PriusChat mobile app.
I have road sign assist on my 2020 Corolla and honestly it's kind of pointless. It only fully works when you are on the cruise control/lane trace screen and even then it's not that helpful. Really the only useful TSS 2.0 feature that is missing from the Prius is the lane trace assist which is really nice.