depending on their sales expectations they could legit make this a loss leader.

I don’t think they will. The problem is that the hardware is open.

Closed-system console vendors can sell at a loss because if you’ve bought the console and don’t buy games from them for it, you’re going to have limited use of it. It’s maybe an expensive Blu-Ray player or something. Not a sensible purchase. You’re gonna buy games for it.

So they can just crank up the price of games and make their return over time from games.

But if the Steam Machine is sold at a loss to undercut mini-PCs, then people will also buy it to use it as a regular mini-PC, and Valve doesn’t make a return from them.