storywriter27 Sorry for the late reply; it looks like your post was moved here from elsewhere after the fact, or perhaps caught in the spam filter.
Please first confirm that all your graphics options (except for water and high-detail lots) are maxed out, and that Advanced Rendering is enabled. If not, change the appropriate settings at the Main Menu, then quit to desktop before loading a save.
Please also let me know whether your RTX 4070 is listed in DeviceConfig. I would guess it is since you otherwise would have asked why you saw a different GPU there, but I want to make sure.
If this doesn't help, please provide a dxdiag. Click Windows key-R, enter dxdiag in the run box, wait for the scan to finish, click "Save all information," and save the file to your desktop. From there, you can attach it to a reply using the paper clip (Attachment) icon included with the other formatting buttons.
I will say that some of the blurriness/pixelation is normal for Sims 3, unfortunately. HQ mods, basically custom GraphicsRules.sgr files, can help, but they also increase the demands on the game engine to a point that you might see performance tank even on your high-end PC. So it would be best to see how much improvement you can get out of other changes first, and of course to make sure there's nothing about your computer itself that's contributing to the problem.