I just played Skylines last night via Proton-GE. AMD GPU. Fedora 43. Gnome.
Also are you running th Linux native one or the proton version?
I run everything through Steam with the proton compatibility layer forced. It's a steam client option somewhere.
I think they're an app called ProtonQT or something like that. It will enable you to easily download the latest proton-ge version. Once downloaded and installed you will need to restart the steam client, then restart the steam client again after selecting the new proton-ge version as the default.
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