Well, I was kind of hoping the patch today would have fixed this one, but alas...
There are a couple of confirmed bug reports for this exact issue. For some reason I can't post links here, but here is a workaround I have found that has worked for a lot of people...
I had the same issue. I have an RTX 4090 and am running default High on 3840x1600. What I did was go into advanced graphics settings and set my MIP Bias from 0 to 1, and the blurry texture issue cleared up immediately. Setting back to 0 and the textures went blurry again. Set back to 1, 2, or 3 and the textures loaded fine again. The settings page changed from High to Custom when I changed the MIP Bias setting, however when I restarted leaving it at 1, the Texture Quality showed Medium. I also tried just changing Texture Quality and letting the MIP Bias change with it, but no matter what I chose from High to Very Low, the textures remained blurry until I manually change MIP Bias off of what the preset was.
High =0
Medium=1
Low=2
Very Low=3
What is interesting though is that I helped out someone else having this exact same issue, but their default was set to Medium, MIP Bias 1, and they changed it to MIP Bias 2, and their issue cleared up as well, so it appears that just setting the Default Texture and letting MIP Bias stay with the default for Texture Quality did not fix the issue.