@wongzilla101 - The problem you are facing there isn't with your graphics card, that and the rest of this hardware should be over the top great for TS3 on Windows with some minor care and tending to in the beginning such as getting fps rates capped. And yes, if your Mac is running Catalina for the macOS, that would explain why it is impossible to install or run the Mac version of the game currently as unlike Windows or the prior macOS iterations, Catalina will only run 64-bit applications. TS3 is 32-bit only. A fix for that has been promised by EA and, as of a few days ago, has been reported to be delayed but still in progress.
Anyway, the problem as described is that the UI for TS3 is not resizable and does not scale down properly. I take it you are talking about the scenario where the sims may look fine but you need a strong magnifying glass or two to actually see the interface? The solution there should be to alter the screen and/or the game's resolution to a less strong one (meaning make everything larger) as on the ultra high ones this is unfortunately bound to happen. It's really more of a programming/design shortcoming than a hardware issue because when the game was designed in 2008-09, no one really envisioned trying to make it run on 4k or higher resolutions.
Edit: Bah, or you could do what @puzzlezaddict said, which is the same thing using about 85% fewer words and today, at least, she seems to be typing faster than I am. :)
