Bitcoin Testnet has such a difficulty adjustment but it introduces a lot of quick blocks being mined simultaneously.

For starters, this isn’t that big of a concern since a huge overnight hit to the hashrate would indicate something far more serious than just a climate event happening, perhaps a nuclear war. If that happens, I’m not sure if mining would continue happening since every country would either be annihilated or imposing martial law. Hence, I don’t think it is worth a hard fork.

This also introduces the possibility of miners trying to game the system by intentionally mining periodically to ensure that they try to get as many low difficulty blocks as possible. Either of this would not be good to Bitcoin.