Nintendo's forecast is 153.8M by the end of March '25 with 12.5M units shipped within the current fiscal year. In a worst case scenario sales drop ~50% when the successor will be announced. This would result in ~6M units shipped during fiscal year '25/'26.
So I think it's likely during summer 2026 that Switch surpasses 160M units shipped. Until the end of 2026 there should be 160M units sold to customers.
Switch outperformed any of my worst case predictions, though :D