It seems some people really overestimate how games should perform. This is probably partly due to the insane success of a lot of the top sellers on Switch (and other massive games across other platforms). Not everything needs to sell 5mil+ in order to succeed or perform well.
ARMS for example sold 2.6 million, which is just fantastic for a new style of fighter. It just missed the mark to be in the top 20 best selling fighting games of all time, where it has to go up against juggernauts like Mortal Kombat, Street Fighter, Tekken, Super Smash Bros. and Dragon Ball (which are also pretty much the only games represented in the top 20). Expecting it to beat the founders of fighting games on the first release is unrealistic.
Astral Chain, as others have mentioned, sold above developers expectations, selling over 1.2million and they are making 2 more games for the franchise at least. In comparison, the switch version Bayonetta 2 and Bayonetta 3 sit at just over 1 million at the moment.
For me personally, I expected more from Mario Maker (the first one on the Wii U), considering the popularity of 2D Mario and building games, even though it was the the 7th best selling first party game on the Wii U. The second one however, almost doubled the sales, so it's a far fetch to call it underperforming.
I do think Pokémon Snap performed below developer expectations, but it's no surprise. Part of the reason Snap was popular when it first released was that it allowed people to see Pokémon in 3D. That's not a novelty anymore though, so you're just left with a small on rails 'shooter'. A €39,99 price point could've increased sales a bit, but I'm not sure it would've sold enough to make up for the 30% price difference.
Mario + Rabbids - Sparks of Hope also underperformed according to the developers. I think we can all agree Ubisoft misread the market though. All their games go on crazy sales starting even 1 month after release. The first game had a permanent price drop to €39.99 before it reached 1 year on the market, had multiple sales after that and went as low as €9,99 a couple times. Why on earth would you pay full price, or even at the initial price drop? (I did buy it, but I'm not the average gamer)
Sushi Striker definitely underperformed, and again, completely misreading of the market. Insanely high price for a game in a gerne you can find hundreds, if not thousands of versions of on mobile or web-based platforms.
