From the linked Ask HN.
Hardware is irrelevant if the software isn't comparable. I'd like to be proven wrong but if nothing has changed in the last years there are no real alternatives to the Pi.
Ex lease mini desktop Dell/Hp/Lenovo Intel machines off eBay can be good, and first class Linux support, and cheaper than raspberry pi.
Some applications can be replaced with a microcontroller like esp32 which has excellent software support.
Many of the machines above have pretty average Linux support but it seems to be improving, depends on your application.
If you mean "gives me a standard linux distro I can install software on that can talk to the network and maybe show a UI on a screen", pretty much anything works (and a lot of things people do with Pis are just that - running things like network-wide adblockers, 3D printer servers, small python scripts for whatever).
If it's somewhere in between, it again depends. E.g. if I wanted a MIPI camera, I'd probably track down a RPi and use that unless I could find someone documenting a precise setup on something else.