The 3600X, 3700X, 3800X, 3900X and 3950X all perform the same in games. The 3900XT will not be faster in games. That CPU is a workstation CPU that you buy because of the high cores count for editing stuff etc. Your 3700X is more than enough.
The Ryzen 5000 has a 19% IPC increase over the Ryzen 3000. If you want to upgrade you will have to go for a Ryzen 5000.
Games are ok with a 6 cores 12 thread CPU right now and yours is a 8 cores 16 threads. That CPU is fine for now and the near future or until games start using more than 8 cores. Which is not soon.