Are you having issues with Red Dead Redemption 2 on either the Steam Deck or a Linux desktop with an AMD GPU? Well, upcoming driver updates should improve it. While there was an update in Proton Experimental recently that fixed the game not actually running after the FSR2 upgrade, it seems there's still problems with it crashing after a little while.
Looks like it's possible that will be solved as well soon though! An update (thanks Phoronix) was recently merged into the Mesa drivers for RADV (the AMD Vulkan Driver) that enabled a "unified heap on APUs for Red Dead Redemption 2". This came from developer Samuel Pitoiset (Valve) and inside the request it mentioned how it "Fixes memory explosion with RDR2 without hurting performance as my previous attempt did.".
So with Mesa 22.3 that's due in November it should be a much nicer experience. However, for Steam Deck specifically, Valve might just pull in the change and have it up in a Beta update as I imagine they want a high profile game like this to be sorted quickly.