The trouble is you can't actually scale that way. You might be able to make a 5GHz dual core that can match a 2.5GHz quad core, but nobody can make the 80GHz dual core that would be needed to match a 2.5GHz 64-core. Good luck even making a 5GHz 32-core unless you want to measure power consumption in kilowatts.

Meanwhile if all you need is single thread performance for lower core counts, that's Ryzen rather than Epyc, but it's not like they don't make that.