It isn't about two years, it is now. This console generation isn't selling at a loss, so all that is really happening is that MS and Sony have developed two entirely proprietary OSes with proprietary APIs and locked down distribution and usage, when under the hood they are just normal x86 based systems.
I think it really shows the absurdity of modern consoles in general. The industry made sense from the 70s to 90s when you needed heavily specialized hardware with finely tuned pipelines and exact design specs to be able to do real time video in 2 and eventually 3 dimensions, but today any computer can do that for fairly cheap, and console technologies are not entirely novel hardware concepts, but just cpus and gpus bundled on a board just like every other modern computer system.
If you want an argument for SteamOS, it is that coupling physical parts with a proprietary gaming platform is unnecessary and ridiculous today. So SteamOS doesn't do that. It is a console OS for any computer, in the same way the PS4 and Xbone operate, except you can just build your own rather than being shackled to hardware.
So you are still shackled to a proprietary software platform (Steam) but can console said platform anywhere it supports without being bound to silicon and copper.