Here's an interesting little data point for you, as the developers behind the polar exploration and survival game The Pale Beyond have given an update on Steam Deck engagement with their game.
In a recent video from Bellular Studios, who run the Bellular News YouTube channel, they showed off that 5.28% of players overall were on Steam Deck. The video went up on Nov 24th, 2023 and it's mentioned they're recent stats and Michael mentions in the video how they were "absolutely god damn shocked just how many people were playing on Steam Deck".
The Steam Deck bit starts around 4:37 which is where the video embed below should start:
What's interesting though is this is not the first time I've covered it. Looking back on it, they also said back in March this year how Steam Deck sales were at 10% but that was quite early on after release and the game has now been out for around 9 months. Seeing over 5% of players actually being on Steam Deck though seems like a pretty good number, and far above macOS.