The "alltogether" command is a little backwards. If you use: STEAM_COMPAT_DATA_PATH="/home/deck/.local/share/Steam/steamapps/compatdata/230410" %command% -cluster:public -registry:Steam then it works, and should even if you use SD Card since compatdata is always on SSD. Therefore, all together, together, this is the fix, credits to Nuanulla and Reddit's kooleech, with some adjustments from my own tests(I for example use the Launcher instead of the direct game to get updates):  
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