The ryzen 2700X is the best binned chip which can be overclocked to the 4.2-4.4 range.
It sports 16 threads but most games will not effectively use more than 4 of them.
Today, the best gaming cpu is the I7-8700k with 12 threads and an overclock in the 5.0 range.
Most games depend on the performance of the single master thread.
Partly, the reason is that it is simpler to code a single threaded game.
More technically, look at Amdahl's law to see why many threads give diminishing returns:
https://en.wikipedia.org/wiki/Amdahl%27s_law
Soon, if rumors are true, there will be a I9-9900K with 16 threads along with a I7-9700K and i5-9600k that are supposed to be better overclockers.