I have the same AMD processor Ryzen 7 3700X and I am using a Coolermaster Hyper 212 EVO with the fan that came with it and one High CFM fan (Push-Pull configuration) to keep my processor from getting too hot.
My temperatures fluctuate between high 40c to high 50c all the time while at idle or doing normal computing use. But I have a huge amount of background services running besides the normal Windows background services.
But my temps are similar to yours with only 2% -3% CPU usage.
I don't worry about it unless my Temperature starts running above 80c most of the time. Then I will start troubleshooting the CPU cooler.
The 3700x Maximum Operating Temperature is 95C. So if your temps are below 80C I wouldn't worry about it. Seems like the Ryzen 3000 series run normally hot.
By the way my room temp is generally around 79F - 80F.