I think that was a joke.
It actually was not.
Like others stated, considering Steam OS is Linux in a Nutshell, a port is actually very possible now.
How long it will take, I have no idea, you would have to ask someone who has experience with porting stuff to linux.
Now Blockland runs on a Highly Modified version of Torque, from what I know, there is aversion of TGE for Linux, however you can not just copy and paste code to get something to work, and even if you could there would be errors everywhere, or it would straight up not work at all.
From 2007 to 2014 Blockland has changed very much, and when your working with a bare-bones game engine I can only imagine how long it can take to port something that has had many changes.