We've been thoroughly impressed by Sony's latest controller, the PlayStation 5 DualSense. It's got sweet adaptive triggers, and its haptic motors and microphone can combine to let you play the soundtrack to Doom. They're good for games too, apparently. And now, the latest version of the Steam client beta adds "initial input support" for it, noting that, "Advanced features such as rumble, trackpad, and gyro are not yet supported."
It's a start. Even if you're not using the beta client, using the Define Layout option in Steam's controller settings will let you plug in a DualSense and get it working, minus the advanced features. The open-source community tool DS4Windows has early support for it as well.
It's tempting to interpret that "not yet" in the Steam client beta update notes as a suggestion the controller's full feature set will be added soon, but of course it's also up to game developers to make use of those features once they're accessible.
The Steam client beta update also fixes an issue with Xbox Series X controllers each showing up as two separate controllers, certain game manuals opening inside of Steam client instead of in your browser, shelf dropdown rendering from displaying without a background, and blank UI windows appearing at startup on some systems.