A slow gaming PC that is small and can turn on my TV is still... a slow gaming PC. And one of the main PC benefits, upgradeability is non-existent for the parts that matter (e.g. GPU, VRAM, etc).

You're firmly in the build-a-pc bracket. Nothing else will ever make sense.

I'm still gaming on a 980. I have never been chasing pixel perfection or the latest and greatest.

I would say I am the exception, but hardware survey says otherwise. There are a lot of people for whom the Steam Machine would be at worst a sidegrade.