I think there's less motivation to scalp the steam machine than there was e.g. the steam deck or the PS5. With the PS5 there were all those PS5-exclusives where you can either get a PS5 or not play them. The Steam deck was the first of the current wave of practical PC handhelds and it was a while before there were realistic competitors.

The Steam Machine is ultimately a mid-range gaming PC in a nicer form factor and a slight discount compared to building it yourself. I don't think anyone would pay 1.5x for a Steam Machine when they could just buy a regular PC for less. There's no capabilities the Steam Machine has that a regular PC doesn't, which limits the ability of scalpers to charge larger margins and thereby limits the motivation.

As for potentially impacting the wider PC hardware market? Well, retail scalpers are small fry compared to Altman, Bezos, Musk et al.