The Iranian Air Force in its current condition should be a cakewalk for even the UAEAF if they are led by experienced and dedicated leadership. The issue has to do with the combination of military and political leadership within the GCC that is either focused on relatives of their ruling families or sycophants.
The result is that the commanders arent the best that should be at the helm.
On the other hand, the Iranians too have leadership issues where the blessing of the Ayahtollahs gets in the way of appointing the best of their class.
However, if one looks at the current opening up of Iran after sanctions; with S-300 and local IADs coming online and perhaps Su-30s or Mig-35s being produced locally; the situation will change.
At the end, the Iranians will hold the edge due to any likely conflict being over their own airspace or over the straits.
Still, it is unlikely that such a conflict will not have US involvement at least in terms of support and naval firepower. Which means that the IRIAF will be focused on just keeping Iranian Airspace clear.
The biggest issue with GCC airforces is their lack of forward operating bases(
although UAE has taken steps in this regard and there are rumored FoBs being built near the northern Peninsula coast) . Iran on the other hand has a well built infrastructure of FoBs that came up due to the 8 year long conflict. Their forces are more geared to disperse and regroup at forward locations. This means that Iranian pilots will endure less fatigue as compared to many GCC pilots as they will fly closer to recovery locations and over their home front.
It is important then for the Saudis to take the lead in creating a forward operating Nexus or work with the UAE to purchase a substantial tanker fleet in comparison to their fighter fleet to allow for constant CAPs at such distant locations along with strike radius.
Assuming that Iraq will remain neutral now and carry a balancing act looking forward; most engagements are over the Persian gulf which basically hints at a war of attrition based on coastal barriers both in the air and sea. Almost mirroring the Iran -Iraq war of the 80s.
Unlike that conflict; the first world powers might like to sit this one out since both China and Russia have interests in both Saudi Arabia and Iran. The US will be the game changer in such a conflict.
On their own, the current GCC vs IRIAF is imbalanced well in the favour of GCC but requires effective leadeship within the GCC to be able to avoid the home front advantage that Iran has. The current Yemen conflict is only winding down after US assistance in blockading Iranian Arms and personnel shipments to the area. On their own, GCC leadership was unable to prosecute the conflict in an effective manner and generally the results have been just hammering away at militant targets without any quick gains achieved by knocking out key nodes in a systemic manner; almost as if the Yemen intervention was unplanned and adhoc.
If such is to be expected in a conflict with Iran(unlikely as the RSAF and UAEAF plan regularly specifically against Iranian targets), then the result will be a drawn out stalemate.
I also want this Saudi Irani rivalry to come to an end. It is dividing and damaging Muslims alot but you can see for yourself here the Irani members are full of hatred against Saudi Arabia. They dont want peace so they will continue to bark against Saudia till they die and their children will also do the same without any success. the problem lies in Iran not Saudi Arabia.
The same can be said of Saudis, you are biased and not seeing the bigger issue of ancient Arab-Persian rivalry. Both sides have played dirty and their hands are bloodied with the filth of using extremist ideals to fuel proxy conflicts.