@SimmerGeorge The fps you've listed is somewhat low for an Nvidia 1060. The game itself has fps drops, including when there are a number of sims on the current lot or when you're playing in San Myshuno, because of how it's programmed, and that can't really be helped. But in theory, you should see fps more like 80 at its lowest and ranging much higher. So there's likely something else going on.
Of course, higher fps doesn't help if your monitor can't display it, but you should definitely see a smooth 60 fps (if that's your monitor's refresh rate) with v-sync enabled. If you're up for some testing, there are a few things you can try, with v-sync disabled for now at least, so you see the true max fps.
Please undo the GeForce Experience setting to optimize Sims 4; you can set your options manually. Disable Origin in-game as well: hover over your username, select Application Setting, then the Origin in-game header, and disable the first option at the top. Move your entire Sims 4 user data folder out of Documents\Electronic Arts and onto your desktop; when you launch the game, a clean folder will spawn with no content. (Don't add anything to this folder yet.) Set your graphics options to ultra if theyr'e not already, and disable post-processing.
Test in fullscreen, windowed fullscreen, and windowed modes, both with your normal setup and with Origin and your computer offline. Don't run any other apps while testing. Let me know whether you see any improvement.
If none of this makes much of a difference, please run a dxdiag and attach it to a post.
https://help.ea.com/en-us/help/pc/how-to-gather-dxdiag-information/