It's quite an open and honest post about the state of things, noting that they didn't really do a good job of actually supporting the Linux version. The post mentions how they never routinely tested it, unless they knew something was wrong. Newman also mentions how the "quiet majority" of Linux gamers accept that they're often a second-class citizen but we shouldn't be as we are paying the same. Which is why they made the decision to stop supporting Linux originally in July last year.
Their plan for the Linux version going forward is to split it away from Windows and Mac, along with getting no new features but it will see "maintenance patches". So Linux owners can still play it and play online together, but not with Windows and Mac players.
Facepunch will also not work on any future Linux games, as they "can't/won't properly support it".
A shame this happened, but nice to finally draw a line under it and know exactly what's happening.
If you are after a survival game that's supported on Linux, I can recommend 7 Days to Die which is really good fun [Humble Store - Steam]. Our livestreamer, Sin, regularly shows it off on our Twitch Channel.