Harden hasn't had an edge over Curry as MVP for awhile. Not especially after his horrible showing in their previous matchup and losing by another (effective) blowout last night. Rockets are 0-4 in their meetings this year. That's not a great narrative for Harden over Curry.
That's before we even get into overall stats, efficiency, assists, +/-, advanced stats like RPM, RAPM, VORP, team record, ranking, etc etc.
Oh, we're you talking about cover athlete candidate? I don't quite see that either. He's not quite as universally appealing (and can be specifically unappealing in some ways to basketball fans).