I would bet that they aren’t losing as much money as other companies would. Valve made their own OS for the Steam Deck. Asus and Lenovo made similar devices, but they both run Windows and have to pay Microsoft licensing fees.
It’ll be really interesting if Valve opens up a partner program with other OEMs to allow things like firmware updates through SteamOS on more devices than just the Deck. I think then, we’d see $500 or less competing consoles to the Deck.