Unlike Nintendo/Sony/Xbox, Valve is selling an unlocked system. Nintendo, makes 30% of all third party games sold for Switch and keeps 100% of their profit on first party games. They can afford to lose money on hardware.
On Steam Deck you can install other storefronts, freeware games or even Windows and just use it for spreadsheets. Plus you can pull the HDD and use it in something else. If Valve sold it under cost, businesses and individuals would be using them as thin clients, or servers, or anything else an unlocked PC can do. Sell it far enough below cost and it's a cheap source of parts. Valve might have a big hord of wealth, but losing money like that could bankrupt them surprisingly quickly.
Meanwhile, Valve doesn't want to sacrifice the goodwill they got from releasing an unlocked system. They do want as many gamers to have them as possible because a lot of them are using it for Steam games. This all puts Valve in a difficult place.
I think the high price is mainly an indicator of how f*ed everything is right now. I've been looking at building a PC for a while and prices just keep getting worse. It's clear from the Steam Box delays and the Steam Deck being sold out for months that Valve didn't get their order in before the shortages, and now they are stuck in the same situation as the rest of us.
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