We'll see for this year but it is almost sure it will peak. If Nintendo pushes it enough it could do over 22 millions. But with a price cut and strong lineup I think some people will be surprised at how well it will perform. Its momentum is stronger yoy and that's compared to a 20+ million year... dont think anyone saw that coming and even didnt see it reach 20 millions before like fall. Feels like switch has just been breaking expectations since day 1.
It will be the first console since the Wii/DS to achieve multiple 20+ years. Outstanding.