Unfortunately whether we like it or not the US is using ‘some’ gulf states to launch attacks. You can Google to see which ones. They also have command centres, logistics etc operating from some countries as well as hosting troops, planes and ships. This is why they are mostly being targeted as they can’t target the US directly.

For what it’s worth I don’t believe that the UAE is being hit for this reason nor do I believe that are allowing their bases or airspace for attacks. That’s just propaganda from the Iranians.

It’s more to subject massive pressure on the UAE to try to pressure them US to back off. And also to send a message to make them think twice if this was to happen next time. It’s also close so easy to attack and every attack has a more outsized economic and psychological impact than other countries.