The Ethereum "ice age" is a mechanism to ensure smooth transition to future planned hard forks. By tweaking the difficulty adjustment formula to artificially increase block times after some time (the so called "difficulty bomb") it makes mining on the old chain unprofitable, and incentivizes everyone to move to the/a new one. The general idea is to prevent extreme conservatism and stagnation w.r.t. hard forks, as we are seeing in Bitcoin.
Incidentally, in Bitcoin, large mining pools do not have control over the consensus rules. It doesn't matter what the miners say, their chain is worthless if people refuse to run it.
In Bitcoin, the economic majority decides what is Bitcoin. And when there's a substantial disagreement (e.g. BCC) there's a fork.
Large mining pools have no more power to enforce consensus rule changes on others than anybody else does.
The former offers far more visibility than the latter for say in the future.
So yes, IMO it is.
Otherwise private concentration of power will do as it always does: leverage it's monopoly to control the system as a whole.
The discussion & development are in the open. The large mining pools can sit at the table and discuss the changes as a part of the community. Or fork off.
