The Switch definitely has a good shot. From what the trends are pointing to, this year is likely to be flat from last year, but imo, I feel that 2022 will probably continue to hold flat from both 2021 and 2020. Nintendo has already committed to 2 major 1st party releases, namely Poke: Legends and Splatoon 3, thus indicating that they plan on continuing strong software support for the next year. In addition, the release of a new revision and Botw 2 sometime at the end of this fiscal year should lead to unmet demand being filled next year.
Therefore, the possibility for 3 consecutive high 20M years for the Switch should not be discounted, as that would imply both a release date for the Switch sucessor of no earlier than Holiday 2024 (Time for the new software and model revisions to sell their due course) and culminative sales in the ballpark of 130M by the end of FY 2022, which barring divine intervention, would certainly put the Switch on a clear path to take the crown.