Run your games or programs and see what the gpu and CPU usage is at. If the CPU is hitting 100% then it would be a worthwhile upgrade but if the gpu is hitting %100 it wouldn't do much. If they are about even, play at low settings and resolution and if the fps goes up a significant amount you could upgrade to a 3060 or something in that range.
Total cpu usage is fairly meaningless, you can be cpu limited even when total cpu usage is not 100%. It only takes a few or even 1 thread hitting close to 100% to be the limiting factor even if other threads have much lower usage.
Id suggest monitoring all cpu threads and the usage. I would also do a test, drop the resolution, if currently using 1080p then try 720p. If the fps stays about the same then it’s likely the system is cpu limited, if there is a noticeable increase in fps then it’s likely the system is gpu limited.
My expectation is the system is already gpu limited unless running a very low resolution but let’s try and prove that.