Carbonvote is an informal vote. It has no consequence in reality. That's why there was such a low voting rate.

As of now, the amount of ether you hold doesn't increase your ability to affect a fork. That's entirely controlled by miners. The amount of computing power you bring to the ethereum blockchain controls how much your vote counts.

If Ethereum switches to a "proof-of-stake" system as planned, then yes, the amount of ether you hold will effectively be how many votes you have in making decisions like these.