Gulf states refuse to be launching pad for any US attacks against Iran

Fear of Iran is not the motivating factor for Gulf states closing their airspace.

Iran would be especially stupid to target other states' oil production as that would only foster a unified front against them and harm their own agenda.

The Gulf states just don't want conflict in general, smell a potential for escalation, and can see the U.S.'s weakening position. Also the U.S has been buying less and less oil from SA.

If Iran strikes first, that would be a different story, but for now, they are fighting entirely through proxies.

So the U.S. is also limited to targeting those proxies, or using their own.

The U.S. wouldn't use B-52's as a first strike anyway and don't need access to the aforementioned airspace to do so.

This airspace limitation is a dog and pony show. At least for now. If the U.S. keeps warming up to Russia, that may cool some heels on the Iranian front, but would also further exacerbate their strained relationship with the Gulf States.

Long story short, Trump's policies are making everyone hate the U.S. except for Israel and Russia. And that is fucking wild.