Why create more faster processors despite of Processor Memory Bottleneck?
Creating faster processors with more cores makes sense because more speed and more cores is not the only change.

Big changes are: 


Bigger caches. Ryzen Threadripper has up to 288MB of cache. My iPhone has more than 16 MB of cache. Your processor can do an awful lot of work without ever touching RAM. 
More memory bandwidth. Data transfer has gone from 32 bit to 64 bit to 128 bit to 256 bit transfers in parallel and not stopping there. 
Improved streaming. The time needed to move consecutive data is very much improved, so the right algorithms can process data at massive speed. 
Changed algorithms. If I know that memory access speed has become the bottleneck, then I can change algorithms that were optimal with a processor of ten years ago to be optimal on today's processors.