DXVK is part of the secret sauce that helps Valve's Proton to run so many Windows games exceptionally well on Linux, and DXVK 3.0 brings some big advancements.
Just ahead of the actual proper launch of the Steam Machine, it appears Valve have rather quietly tweaked their wording on the expected performance from it.
Want RAM prices to fall? Don't expect it soon. Micron recently announced they've signed 16 SCAs (strategic customer agreements) across five-year terms.