[ameliaquining]

It's not the first time Ethereum has hard-forked to roll back a sufficiently bad bug in a smart contract, and it probably won't be the last. They periodically do hard-forks for other reasons as well. Eventually they might declare it 1.0 and stop doing this, but that's not how it's managed today. At this point I think users accept this as a risk of using Ethereum. Of course anyone who doesn't like it is free to try to keep the old chain alive (indeed, Ethereum Classic is still a thing that exists).

[cslarson]

Ethereum Classic also hard forks in order to make changes and other upgrades to it's protocol.

Ethereum has not yet hard forked to enact this proposal. At the moment it looks very unlikely to gain the support needed.