Remember that Nintendo said that Switch is in the middle of its life already in 2020. I think that Switch reached about 60 % of its lifetime. A successor usually launches at 80 % of a console's lifetime. In the last 20 % of a consoles life you don't sell that many units anymore.
If Switch is able to reach 160M depends on when a successor launches. If we really get Mario Kart 10/Crossroads for Switch in 2023, then DLC should come in 2024 and a successor should launch in 2025 with Mario Kart 10/Crossroads Deluxe (incl. DLC). If we only see Metroid Prime 4 as the big title for 2023 or just a few smaller Nintendo titles, then we know that Nintendo is holding back games and a successor launches in 2024 - and then I don't see any chance for 160M. I don't expect a more powerful hardware revision anymore.
If 2022 sells below 20M with Zelda BOTW 2, Splatoon 3 and Pokemon Arceus, a successor is very likely in 2024.
There is a small possibility that Mario Kart 9 releases on switch but 10 will not.
I don't know why the rumor says Mario Kart 10. Maybe Mario Kart Live counts as 9.