Are you sure they aren't just telling you to turn off the CPU portion of their miner, so it only uses your GPU's?  That's how I would read that - not that they're telling you to turn off your rigs.

I think it's pretty unlikely that they blocked your IP because of the post, I've made positive and negative posts about Nicehash, and have never seen a comment one way or the other.  They do have some kind of automated temporary banning of IP's if your miner is misbehaving, and I have run into that a long time ago, but if I remember it was reset after a few hours.