Okay, in case this helps someone: on Steam, if you use WebView2, never enable the ‘Steam Export’ option when creating the build, no controller except Xbox controllers will work. It probably conflicts with the Overlay. But since the Overlay is only needed for screenshots, it’s something you can sacrifice.
I got a negative review and several critical feedback reports because of this, so I strongly suggest adding a VERY LARGE AND CLEAR warning for anyone deciding to use Steam Export during the build process.
Also, I suspect that many of the unusual chargebacks in the last few days were caused by this as well… really frustrating, and I don’t understand why such an option exists if it can compromise months of work.
Anyway, those are my two cents.