To the OP, I think it has nothing to do with the definition of porn or community standards. Its the porn industry itself. Hardcore porn doesn’t need to advertise. If you want it, you are going to find it. I think advertising works for S.I. and G.G.W. because people who would not respond to an add for Backdoor Sluts 9, might order Girls Gone Wild just because they saw the ad. Its easy to consider Girls Gone Wild as harmless fun, porn-light if you will.
I didn’t know if it was that, or it the FCC didn’t allow hardcore ads. If they do allow them, I find it odd that no hardcore film company has ever wanted to advertise anything on TV, ever, even pre-internet.
I wouldn’t think that the FCC can decide what products can and can’t advertise as long as the content of the ad itself was not obscene.
And the FCC has no control over cable, just over the broadcast networks.