My hope after seeing that the joysticks themselves look like they can be removed from the main board is that the touchpads can be relocated to the top without too much hassle and put into a 3D printed top shell made by the community. So if that were possible what I'd probably do is pop off the XYAB, dpad, and board holding the joystick so the touchpad can be moved up to make the touchpads comfortable for primary use.
And then I'd rely on the back buttons and set up a dpad modeshift on a right pad click to enable edge and center clicks, so I wouldn't miss the absence of the other inputs too much. I also use touchpad for movement where I'll often set outer ring to sprint and map crouch/slide/dash on touchpad click, so cuts down on needed inputs further.
So that's my hope that modifying the new Steam Controller for touchpad users will be as simple as 3d printing a shell and opening the controller and not require further things like soldering.
I don't think their hardware sales becoming insanely profitable is their main goal and their focus on the finance side might be to at the very worst break even.
Their main goal I believe is to try to increase Linux usage so the holdouts against it might start allowing their games to run on Linux, and devs may feel that with Stean machines out there that can run their more resource heavy games better than the Deck it is worth it to pursue proton compatibility.
They probably learned from the mistakes they made in the past when they pushed Linux adoption attempts on to third party companies. They realized they needed to provide some standardized hardware instead of leaving the work to others if they wanted Linux to start being taken more seriously among devs with how small the userbase still is even with the Deck success.