There are a lot of times where an airbase would be necessary on Egypt or the Persian Gulf just because you are trying to protect whatever blocking fleet is over there. But a superior move would probably be building better units earlier, and more UK factories early, if you can afford that because the airbase probably isn’t going to be saving you just delaying the assault.
The defensive geometries of the ME are awkward, you cant get defensive flyers to Egypt from India, or vice versa. You cant reach Moscow from Iraq without one, or from Moscow to India. Even the airbase on Egypt is 1 move short of Moscow. That means that an airbase doesn’t remedy most of your movement issues, it would be for scrambling and defense.