If you want to utilize all features of an 8BitDo controller at once, you also need Steam. XInput mode means no gyro, no back buttons bindable in software, Switch mode gives you gyro but makes your triggers digital, and you still can't bind the back buttons in software. You're limited to duplicating an existing input via the 8BitDo app and binding it globally at the firmware level. If you use the 8BitDo Pro 2 with Steam in DInput mode, you get analog triggers, gyro, and the back buttons are bindable in software per-game. This was not the case on release, 8BitDo and Valve worked together and gave this improved support via an update.

The software around controllers is universally bad, and Valve is the first to really try to fix it. We need a successor to XInput that is less limited.

The Steam controller doesn't have Hall effect sticks; they're TMR. Also, my 8bitdo controller does need special software to use a couple buttons on it. And it's the cheapest possible model, not a super advanced one. It just has more buttons than xinput supports.

This isn't to say that you're wrong about your main point. Steam is heavyweight to use just as an input profile selector at application launch. But you should be careful about details if you choose to include them.

I can highly recommend Gamesir controllers. I haven't tried all of course, they make a lot of different ones, but generally it's a great brand for very high quality controllers at crap-controller price. Better bang for the buck than 8BitDo (who focus more on style than functionality).

I've no relationship with the brand btw, I'm just a happy customer.