


Only reason I can think that it would be "unsupported" is the 3rd party loader. Everything runs as pefectly as it can!
Considering this game came out in 2009 and was not designed to run on a handheld PC, it runs basically flawlessly, and the community controls are fantastic. I didn't think I'd be able to cope with having to use the trackpads but, honestly most of the functionality is mapped to buttons and you only really need to use the mouse to tell your Sim where to go and what to do. It runs basically flawlessly. I'm really impressed!

When quiting the game the Sims 3 Launcher will still be open. This is a problem on both desktop and the Deck. You just need to close the game from the Steam Menu
I have nothing to complain about when it comes to The Sims 3 on the Deck. It some how runs smoother on the Deck than on my gaming tower, create a sim loads things way quicker, less loading in general it seems.
One change if you're playing handheld without a keyboard is cheats. You'll need to set 3 different buttons to CNTRL+Shift+C to load up the cheat menu.

adjusted community layout for the greater range of inputs supported on the deck
I cannot for the life of me understand why this is marked as "unsupported". Everything works fine from what I can tell, I changed absolutely nothing, was able to launch the game, go through the launcher, and play normally. Even mods work. The resolution was set wrong, but that's an easy fix.
I still recommend to skip the launcher though:
-browse local files with steam
-enter the Game folder, then the Bin folder
-Find the file: Sims3LauncherW.exe
and rename it to something else
-Rename Ts3W.exe
to Sims3LauncherW.exe
This way Steam will think that it's launching the launcher when you hit play. When in actual fact, you're launching the game.
Community input layout recommended, but otherwise works out of the box on the Steam Deck!
Reduced mouse sensitivity, and changed DPad to be Scroll Wheel
The UI feels quite small for the Deck display but its sill useable
Sim voices crackled in Create-A-Sim sometimes
Lighting seems broken in mirrors
Community input layout recommended, but otherwise works out of the box on the Steam Deck!
Reduced mouse sensitivity, and changed DPad to be Scroll Wheel
The UI feels quite small for the Deck display but its sill useable
Lighting seems broken in mirrors