Zen 4 will have leading performance so ofcourse it will cost more, it will be like Zen 2 and Intel era, if you want best gaming performance, and newest standards like ddr5 you will choose Zen 4, if you want budget option with more cores and better multithread performance you will choose RPL. We have yet to see if Zen 4 will increase cores, they don't need as much as Intel cuz each Zen 4 core is many times better than each e cores, and also lower latency between each of them.