Those PlayStation supercomputers were wild. I don't think it's analogous to the various bits of Steam hardware coming out though, since Valve sells directly through Steam. You can't order anything by the pallet.
The other thing to consider is that the PS3 was used for clustered computing primarily because of the Cell processor. I have no recollection of why the cell processor performed better on certain types of problems. PS3 wasn't being used for Excel spreadsheets, it was used for niche academic use and that one Air Force supercomputer. The Steam hardware though uses pretty standard hardware, AMD processor and Radeon graphics card.
Considering the added friction of buying through Steam, i doubt it will have same draw.
Second installing Heroic or Junk Store. Get those Epic freebies, but games in GoG sales as well.
As you are new with the Deck though, using Heroic does involve using desktop mode. If you have Minecraft, you can set up Prism Launcher as well. There's also EmuDeck for emulating older systems.
This is a bit more involved than just buying Deck verified games on the Steam store though. Get comfortable with it first. Watch some YouTube tutorials.