I am just building a new PC with 3700X and 2070 Super and i have fx 8350 i think it is bearable but I want 144 FPS+ on gta at 1080pA totally unexpected result.
The theory is that by lowering your settings, the graphics card has less work to do and becomes less of a limitation.
If the cpu is capable of generating more frames per second, your fps should have gone up.
Usually, games like sims strategy and mmo tend to depend on a strong single core performance.
Multiplayer games like the 8 threads you have.
Fast action games respond to faster graphics cards.
I suspect you are cpu limited.
To test how many cores are useful to you, here is another test:
You can do this in the windows msconfig boot advanced options option.
You will need to reboot for the change to take effect. Set the number of threads to less than you have.
This will tell you how sensitive your games are to the benefits of many threads.
If you see little difference, your game does not need all the threads you have.
Really, the FX line is all but obsolete for gaming.
Best to plan on a cpu/motherboard/ ram replacement.