Of course an i5 can't go up against a hexa core. But even for "high end" gaming you way as well buy the highest clocked i7 quad rather than a server platform that has been rejigged for the consumer market. The obsession with chasing FPS will only drain your wallet.
Did you read the article I linked to? A 6900K outperforms or equals the 7700K in the majority of titles that they tested (despite having a major clock speed handicap), whilst having much greater utility for things like transcoding, streaming etcetera. The HEDT platform is just much more robust despite being a generation behind.
But it's not for everyone I agree.