So it really is very early to start making predictions about this, but going if I were to make one I'd say that I don't see it happening unless it has an unusually long lifespan.
In fact at the moment I don't think there's much of a reason to believe it will outsell the PS4, since it will have stronger competition in the Xbox Series (it's not in direct competition with the Switch the way I see it).
- Switch - 27m
- PS5 - 15.5m
- Xbox Series - 10m