The diff increase is a mostly a byproduct of MORE FOLKS CHASING THE SAME REWARDS coupled with the (so far small) ARTIFICIAL increase, and not a direct impact on profitabilty (though it does have an indirect effect).
Ice age on the other hand, so far, has had a very SMALL effect on the difficulty.
The Ice Age artificial increase does NOT affect profitability, only the "more GPUs mining" part of diff increase does because that does NOT affect all miners equally, while the Ice Age artificial diff increase DOES affects everyone equally.
I continue to state it is a stupid concept with no real reason to exist, since it affects all miners EQUALLY and doesn't change the rewards gained from any particular block - it's the dropping BLOCK PAYOUT that is effecting that.
It also doesn't affect block rate over the long term.
Consider Bitcoin, which also uses a difficulty system which has gone up a TON more than ETH has yet the block are still targeting the same timeframe to be issued - it's just SHORT TERM that adjustments get made due to diff changes - and in the case of ETH the "short term" is very short indeed.
You might want to consider looking into ALL of the facts before you call someone else ignorant.
It's true the ETH network hashrate has increased exponentially, which cause the rewards to be diluted by all those mining. But since the ICE AGE effects began back in May, the difficulty is artificially adjusted according to programmed difficulty bomb, not the network hashrate. The artificially high difficulty along with the increasing block times most definitely affect everyone's profitability by slowing down the amount of blocks mined in the same time frame. Less blocks = less rewards = less profit for EVERYONE. That's the main reason ETH is no longer the most profitable coin to mine, since the difficulty bomb on August 25th and not because there are more people mining ETH.
Wait until the next ICE AGE difficulty bomb adjustment on September 24th and tell me if has no affect on profitability, LOL. At the current price, ETH won't be profitable to mine AT ALL for most people, until the hard fork scheduled for the end of September that will undue the artificial difficulty bomb adjustments and go back to adjusting the difficulty for the network hashrate along with reducing the block times back to 15 seconds and reducing the reward.