Definitely an outlier. Windows has generally been very very solid since about Windows 7. Certainly since Windows 10.
Linux is still quite far behind in terms of desktop stability in my experience. But I guess if Valve fully controls the hardware they can avoid janky driver issues (it sounds like suspend will work reliably!), so this might actually make a good desktop Linux option.
You are also definitely an outlier. In my experience, Linux has been 5x as stable as Windows (and more performant, too). SteamOS is just Arch Linux with the KDE desktop, the actual desktop stability wont be different from the same setup on a normal PC.
Linux is still quite far behind in terms of desktop stability in my experience. But I guess if Valve fully controls the hardware they can avoid janky driver issues (it sounds like suspend will work reliably!), so this might actually make a good desktop Linux option.