For current devices I'm going to give general predictions of +/- 10%. Switch depends on if they have any major hits outside of Animal Crossing and if they are aggressive with bundles/promotions during the holidays. PS4/XBO depends on if they get official price cuts this year.
NSW-20m
PS4-10m
XBO-3.5m
For PS5/XSX it depends on stock but I think they will supply more than they did for PS4/XBO for 2 reasons.
1. MS is going avoid the "teir 2" shenanigans and Sony isnt staggering the Japan launch so they will need a few 100k for these areas.
2. They want good PR about how they surpassed the PS4/XBO launch sales.
PS5-4.5m
XSX-3.5m
When the herd loses its way, the shepard must kill the bull that leads them astray.