My XSX controller is yet to drift and I doubt that it'll ever drift given that they seem to have a very good record in that regard. What I'm more excited about when it comes to the Steam Controller is that it's more than just another Xbox controller. The Deck haptic touchpads and gyro makes me feel like I could use it do comfortably play shit like GTA, Saints Row and Cyberpunk with analog car steering and precise aim. Also BeamNG.drive where I can bind bazilion of it's inputs to the controller, something I can't do on the Xbox controller so a mouse and keyboard with mouse steering is the next best thing. Technically you could use the gyro to turn the controller into a Wiimote-esque steering wheel.
To me, that's the value Valve hardware gives you. It's not just offering you another option on the market, it's offering you another option on the market that has actually good, well thought out new features. Obviously I see no value in the Steam Machine since I don't need a TV gaming PC and I already spent more on my GPU than it would cost me to get a GabeCube, but the controller and the Frame? Former is a must-have, latter is a definite maybe.