KSA were the ones that cut diplomatic ties back in 2015 when they executed a bunch of Shia extremists/terrorists. Iran had a far too big mouth as usual (meddling in internal Saudi Arabian affairs) and had some local thugs storm the Saudi Arabian consulate in Mashhad (a city founded by Arabs and Mashhad is an Arabic name too like so many Iranian city names) and as a consequence KSA rightly cut diplomatic ties. Rest is history.
This will mean nothing if the Iranian Mullah's continue their nefarious meddling in internal Arab affairs and Arab states that are in crisis or undergoing civil wars as opportunistic vultures. Notice how they are incapable of doing such a thing in stable Arab states.
KSA does not need Iran for anything nor do Arabs need it who are the big brother in this relationship on every front.
Arabs are divided politically and some Arab regimes seem to like the Iranian Mullah's and their nefarious activities. I guess that they like to be failed states. Houthi-ruled Northern Yemen, small/tiny Southern Lebanon and Lebanon as a whole and partially Al-Assad regime in Syria albeit they are now desperately opening up to their Arab brethren again, I guess they learned it the hard way that nothing good comes out of being Mullah partners other than misery.
KSA should just allow Iranian pilgrims for Hajj and Umrah and take the money and refrain from doing anything else with that entity.
Iran is to most Arabs what India is to Pakistan.
Iran has no patent on Shia Islam. Shia Islam is native to Arabia. In fact it were the Arab Mullah's that spread Shia Islam most recently during the Safavids.
en.wikipedia.org
Iranian meddling is a cause of much bloodshed in the Arab world from Iraq, Syria, Lebanon to Yemen.
Arab leaderships have to be insane to trust this Mullah regime.