But in my opinion it would be smarter to find a solution - both for the Playstation players of XIM and for the further business for XIM.
A DualSense controller won't be reverse-engineered by anyone. Smarter people than you or I have already invested the best part of a year into solving this puzzle. If it can't be done, it can't be done.
The only direct hope for XIM is a third-party PS5 controller, but there aren't any on the horizon. Scuf is rumoured to have one in the works, but aren't they just customised Sony controller buttons, sticks and shells? It'd still be a DualSense under the hood.
There are options for using m/kb on PS5 -
1. Native m/kb in supported PS5 games.
2. Remote Play on PC, Mac or PS4 using a DS4 V2 on XIM APEX.
3. PS4 game versions work with XIM APEX.
4. Possible solution from ConsoleTuner. It'll take awhile to know if this works or not.
Or just get an Xbox. Seriously, it craps all over PS5 for shooter games and XIM works in all of them. If you want to use a XIM, this is the smarter solution.
You are a healthy fella with 10 fingers, there is a huge group of people who rely on speciality controllers and they have no longer way to play playstation games anymore.
Remote Play remains an option. I think it's fair to say that speed / precision isn't the primary objection for assistive technology, so a touch of input lag shouldn't be a problem. That said, Remote Play does require additional equipment, so it's not for everyone.
It is anticonsumer of Sony though and just one mistake of many heading into this generation. I understand the desire to protect their adaptive triggers and haptic feedback, hence the heavy encryption. But PS5 requiring games to use a DualSense is a tough call.
I suspect it has more to do with refusing to pay licencing fees for rumble feedback on DualShock controllers than intentionally locking out third-party devices. They needed to make a clean break from the past and forcing a DualSense for next-gen games is one way to do it.