Doesn't really matter. CPU mining will never be as profitable. Whatever hashrate new Ryzen processors are getting they will never hit ROI so there is no point in buying them with mining in mind, and if you want to mine from time to time there is no profit (just a few bucks)
are you serious? do some research, it is true that cpu has lower roi but they will hit it... When zec was out the first 2 weeks were great for cpu miners + ryzen should have greater performance and consumption, I need some cpu to my rig, why not buy on which can earn me money?