If it does close, the Activison acquisition won't go through into much later this year.
Work on COD for Nintendo won't start until after that, and the porting process takes time, so by the time it's done, Switch's successor will most likely have arrived.
There's a good chance that a next gen Switch releasing in late 2023 or 2024 will be more than capable of handling ports of current gen COD.
Bet with Liquidlaser: I say PS5 and Xbox Series will sell more than 56 million combined by the end of 2023. (And over 130 million lifetime)