25Million isn't a big ask for the Switch, we have never seen a console in history have sales drop more than 6 million units the next year unless a successor is right around the corner. If anything the Switch is more likely to sell above 25M in 2021 and I believe that even without this pandemic that the Switch had the opportunity to sell 25M in 2020 with Animal Crossing leading the way and globally speaking the Switch was already up YoY in 2020 before the pandemic started. Plus you have to keep in mind that this virus doesn't look like it's going to end anytime soon heading into 2021. Also, I think there's a chance we see a stronger 2021 year for Nintendo since it's probable that many games planned for 2020 got pushed into 2021 which will help Switch sales. Also the possibility of a Switch Pro and more.
Also, it isn't unlikely that the Switch continues to outsell the PS5 in 2022 and 2023, PS consoles have a difficult time hitting 20M years most of the time and I still think the Switch could sell in the upper 10M to lower 20m in 2022 and possibly 2023, which would be enough to still outsell the PS5 in those years.
2020 was an abnormal year for console sales, even the Xbox One got great boosts, and that's been more or less dead in the water. You can't take extraordinary market circumstances and apply them to the following year, simply counting on another year with the pandemic affecting us like it did this year is problematic as a means to make sales predictions. Seeing as both MS and Sony announced and even showed their new machines, the drops should be staggering, but they really weren't. 2020 is defying almost all sales trends that we currently know and make use of in discussions.
The Wii saw three consecutive years of drops in excess of 5 million, with the highest being about 5.4 million or so, and this was before the Wii U was announced. There is historical precedent for sales drops, and even if the Wii was a completely different machine that appealed to a different overall demographic, it tells us something about potential sales curves. Not to mention that the Nintendo release slate looks quite slim in the coming year, any game that may have been pushed into 2021 from 2020 is likely not high profile and as such won't have massive impact. As for hardware revisions; these are simply the minimum effort required for static products like consoles to hang onto the fast-moving modern consumer electronics market and usually don't provide large, sustained boosts. A more dramatic dip in sales can be turned into a medium one though.
PS consoles do indeed have trouble getting north of 20 million for annual sales, but this deduction from historical data leads us to the inevitable issue that we need to consider the abnormal circumstances of 2020 and the unnatural boost it yielded the console market, which was my main point. Two new consoles won't make things easier either, news value matters quite a bit and 3rd party games will continue to shine on the vastly more powerful platforms as the cross-gen releases fade over the next two years or so. This leaves Nintendo in a somewhat precarious, and very familiar, situation, where they're left more or less alone in providing software for their platform, and this is an area where they have a rather shoddy history with both the Wii and Wii U.
Look, I honestly don't know how things will look, but neither do you (and especially OP), but right now there's nothing to suggest that the Corona-boost will continue well into 2021 and we have no idea how well the PS5 will sell once it's readily available in stores and establishes a semblance of a baseline. If anything; continued lockdowns and suppression leading to massive job losses is likely to weaken the market long-term by reducing consumer purchasing power. What we do have is:
A: Unprecedented market circumstances for all consoles in 2020 (indeed all consumer electronics). There is literally no historical data to provide clues for what's to come, one way or the other (that affects me as well, mind you).
B: We're headed into the part of the console life cycle where Nintendo has had the most trouble in the past two generations. On this, we do have data to analyse in hindsight, right now at this very moment there is little to indicate that dramatic changes are forthcoming here.
All that said, I'm hoping for a closer fight between the PS and Xbox brands this gen; lopsided marketshare benefits no one but the company in question (and the PS4 was kind of boring if I'm honest).
One out of many pieces on how the 2020 pandemic has increased sales of consoles. 36.5% up yoy for the first half of the year compared to 2019, factor in that jan-feb basically saw no changes and that two main consoles should be on the sharp downwards curve associated with being succeeded by new hardware shortly and this is a staggering number. These are not figures to make future estimations on, regardless of platform.