The popularity of the Steam Deck handheld has become highly evident in recent weeks. For the last five weeks, Valve's AMD Aerith APU-powered portable was second in the top seller by revenue charts. However, it managed to move up to the number one spot over the weekend.
These numbers are not all that meaningful though. The device has been backordered since preorders first opened for it back in July of last year, over 9 months ago, and the launch was pushed back at least a couple months, so whatever sales numbers they are showing now are based on how many of those existing pre-orders they can ship out. It doesn't reflect current sales of the device, but rather the better part of a year's worth of sales, compressed into the time period when they actually started shipping them and charging people's cards.
Ultimately, the Steam Deck seems like a relatively niche device, and it's very possible that most of those interested in it already put in their pre-order many months ago, and once the pre-orders dry up it might not actually sell all that well. The device may have had hundreds of thousands of pre-orders, and I imagine it could eventually sell a few million units or more, but compared to the couple-hundred million consoles sold each generation, and a similar number of PCs used for gaming, in addition to a couple-billion mobile gamers, that only amounts to a rather tiny portion of the total market.
Likewise, I would expect Elden Ring's sales are waning at this point, seeing as the game has been out a couple months, and anyone interested in paying full launch price for it likely did so weeks ago. So it's probably less that Steam Deck's pre-order fulfillments pulled ahead, but rather Elden Ring's sales simply fell behind. Making guesses at Steam Deck sales numbers based on pre-order and early sales numbers for Elden Ring is likely going to be hugely inaccurate. And really, there have not been a lot of other big game releases recently, so topping the list shouldn't actually take all that much. The next-highest selling game is currently a Lego Star Wars title, if that says anything.
Quite the opposite, with valve putting so much effort into making windows games run devs won't have a lot of incentive to make native ports for linux.
Yeah, I would expect developers to bother even less with native Linux ports. What is the developer's incentive devote a chunk of their budget and resources to porting the game to yet another platform with a small user-base when things are likely to mostly work even if they don't? A Valve developer commented that any games Steam Deck can't run are considered "bugs", so it's up to Steam to make sure games are able to function on the platform, not the game developers. If a game doesn't run properly, the developer can simply point to Valve for not supporting it adequately.