SteamOS Has Dropped Support For Suspend
jones_supa writes: As pointed out by a Redditor, it seems that suspending the machine is not officially supported by SteamOS anymore. A SteamOS user opened a bug report due to his controllers being unresponsive after a suspend cycle. To this, a Valve engineer bluntly reported that "suspend is no longer supported". He further explained the issue by saying that given the state of hardware and software support throughout the graphics stack on Linux, the team didn't think that they could make the feature work reliably.
To solve this problem, you would need to migrate it all to systemd, and make sure everything involved with the graphics and controllers is using compiled systemd startup modules instead of crufty old scripts.
There are too many parts, and not enough of the upstream has ported yet, so systemd can not (yet) solve this problem. But it will.