Switch should be able to outsell DS and maybe even PS2 we still have no news of a successor, so granted Switch is around 150 million at January 2025, it most likely still has a good 10 to 15 months (if they go for another March launch) left to sell without a successor.
I would estimate Switch could keep selling 500k a month on average the first 10 months. At that point it's at 155 million. So selling another 5 million is not undoable if it gets one more holiday, especially with a cross gen period. That is also assuming all 160 million produced PS2 where actually sold.
Please excuse my (probally) poor grammar