It really depends on what you are trying to optimize for.

If you are doing something illegal or controversial with the key, then yes it would be foolish to store it in the cloud.

If your main concern is it becoming compromised due to a local exploit or physical breach, then I'd argue it is a strong option.

> If you are doing something illegal or controversial with the key, then yes it would be foolish to store it in the cloud.

"Not trusting a private company" does not equate to "doing something illegal or controversial", though.