Owning and still loving the Steam Controller, the haptic concaved trackpads could be set up to really feel like a trackball and, in my opinion, had all the benefits of the trackball without the downsides.
I also use a Steam controller. I like the touchpad so much that I wish there was a stand alone one that I could use for day-to-day computing activities instead of having a physical ball.
I know there are square touchpads you can buy for pointing devices, but the ergonomics are completely different. They are more replacements for finger trackballs rather than thumb trackballs. Like just give me a Logitech MX Ergo with the pad.
I miss the old days of Youtube where people made stuff for fun or because they were passionate about a topic, before the big Youtubers pushing shit out the door to get as many views as they can.
Monetization shifted the focus from niche hobbyist content to gimmicky shit that is tailored to get a bunch of views. When I see a thumbnail of someone with a weird facial expression, it's my cue to look elsewhere.
Steam controller is fantastic, and unfortunately there's really nothing else like it. I normally use a Logitech trackball, so the ability to use a touchpad like a trackball works well for me. I can't think of any other controllers that use this instead of analog sticks.
I've actually stockpiled a few spares because I'm not sure what I would use as a replacement.
Reminds me of the Alpha Grip controller. Has a (really janky) trackball and an entire keyboard on it.