I have been running NW on Linux using Steam for two years with semi ancient hardware, so the steam deck should just be a matter of time. As long as you have the minimum requirements unsupported usually means if it stops working don't cry to us, figure it out yourself.
I am using Proton on steam for NW (pretty sure it is 6.3x at this point), though I have a multilib Wine-staging 6.23 available on system (I use it for another game). I haven't tried the upcoming release. The only annoying issue I see is the chat server cutting out now and then. Graphically I get a bit of tearing and FPS…