I understand it depends on electricity cost and other "future value" thinking but at what price point of ETH, people plan to stop rig?
Under $200 most will quit or shutoff machines.
Many already have.
That is right. The difficulty is dropping now.
If the difficulty is dropping why I don't see it in my results of Nicehash miner, I had 0.55 mBTC yesterday from a rig with 6 Rx 580 cards and I am still having the same reward daily from the same rig ?
Maybe Nicehash acts a little later and that is why I don't see an increase in rewards value from my miners.
With Nicehash you are only being paid for what buyers are willing to spend and not the true value of the hash rate as if you were to mine the coin for yourself. So while the difficulty may be dropping, buyers are most likely lowering their bids and pocketing the difference for themselves.