It is extremely difficult to change course. Countries like the UAE and Saudi Arabia are working on developing the service sectors of their economies so that they can still be competitive without oil and gas exports.
If the day comes when demand for oil and gas is limited, I think they will still struggle. However, it is still possible, out of pure necessity, they could turn move their economies in another direction.
I hope Nigeria is able to change course. The key is offering something other countries want.