Starfield, or other Bethesda type Games, are really “YMMV”.
Colleague of mine still plays it, while i dropped it after some 50’ish hours and having played the crimson raiders arc. At first i had a lot of fun exploring planets for that tasty EXP and getting a Build going.
Now i can Streamroll pretty much everything (Solo build, so no companions) and am fairly high level. Too high level (47 i think?) that Side-Quests with their 100 EXP Reward simply aren’t worth doing when i can get that per enemy on the level 70+ worlds easily without much of a fight.
(Been playing on PC though, for me it ain’t worth it to force myself to play it on Deck but i would’ve if i didn’t have any other means).
The other thing that eventually sets in: You keep repeating the same-ish loop of Exploration which can get old really fast if there’s long streches without any combat or worthwhile lore advancement. Once you begin to see repeats of certain locations and figure out that permanent upgrade magazines usually only spawn in unique locations (which you can see from orbit view after scanning)…
It’s just not worth it anymore at some point.
In regards to Proton:
In my experience, messing with the proton version is only necessary for brand new games. Often Times switching to Experimental already did the trick in case a game wasn’t launching properly. Once a newer proton build for the regular version releases, that can be changed back and games will run… usually.