Thanks for the reply! Before I get into anything else, I'd just like to say thanks for doing what you guys do. Big Box has totally transformed my emulator machine, and I recommend your product to anyone who says they need a way to organize ROMs. Anyways, a few points of response;
That 110k preorder number was in the first 2 hours of the Deck going up for preorder. Preorders after those 2 hours are harder to find, on account of Valve patching the HTML leak that made viewing that number possible. As you mention, preorders are very, very far from a perfect gauge for popularity, but I bring this up only to illustrate the enormous amount of hype around the Deck. Perhaps more pertinent would be this article. If Valve really is producing and selling as many Decks as it seems they are, this is a pretty big deal. Again, the install base will never be as large as Windows or Android (or even Switch), but I'd be willing to bet a dramatically larger percentage of Deck owners will be using their devices to emulate vs Android owners.
Hype and excitement are obviously not enough to engage in the massive undertaking of making a Linux version (as you state, it's certainly not a "chuck it into Proton and call it a day" type of deal), but it's something I'd love to see happen in the future. Whether or not you and your compatriots see it as financially feasible is something I obviously can't speak to, and my input wouldn't be particularly helpful there anyways, but I figured I may as well raise my hand and be counted.
And who knows, if Windows 11 continues to be a garbage fire, maybe I'll finally make that switch to Desktop Linux once 10 is no longer supported...