Protondb has user reports that (usually) include performance stats and settings, as well as any additional setup like launch options or specific preferred proton versions.
I also check Valve’s own “top 100 played on steam deck” list to see what other people are rockin, always surprised to see shit like Fallout 4 on there.
But the entire industry is built around frequent updates and outmoding older models. I had a phone that was no older than 2 Y/O when my cell carrier did some kind of tower update that rendered it completely unusable.
I hate that we’re conditioned to treat these powerful computers like throwaway technology just because a marginally improved model is made available.