You're naming checks with some massive baggage of their own. (Notice the fire-typing? Notice how fire is weak to rock?) Congratulations. You managed to undermine your own point.
I think another problem with Genesect in OU is that it's only weakness (Fire) is generally portrayed as a hyper-offensive type. And yet in THIS meta - the most relevant Fire types are slow and bulky (Awak/Heatran/Volcanion) and get outspead by Genesect (again, going back to running Uturn on every set, making it's MUs far less risky).
PS: How many sets/variations run Explosion these days?