Something you still don't understand is that whenever you try to undermine or go against the national armies of iraq and Syria you give iran space to create smaller forces which gives iran more influence. Today iran has more influence in Syria than it did before the war when the SAA wieled a lot more arms than iran's mililtary. Before 2014 in iraq the mililta's were inactive, the army collapsed and they all grew. You still don't get it? Saudi strategy is very stupid. iran benefits.
No one is going to overthrow Baghdad and Damacus, already tried and failed. To continue with that policy is beneficial to iran.
I agree with you and I'm not saying Al-Saud policy is good. Along with Iran they're part of the mess in the region by fueling sectarianism. Not to forget the rest of Arab regimes who are no more than dictators killing their people to stay in their positions for all their life. This is the main reason of what's happening in Arab world. If all people in Syria were treated good by Assad, no power on this planet can intervene in their affairs ! But unfortunately, ........
Saudi strategy is failing not because they're not working to counter Iran. But people like to change, they no more want to follow the Saudi views, either because of what they see in the media or because Saudi Arabia is working with U.S and the west, or because of something happened in the past (e.g. many Iraqis blame Saudi Arabia for the mess in Iraq after U.S invasion.. many Syrians have the same feeling because KSA supported FSA.. many in Lebanon because KSA is working against Hezbollah.. many in Egypt for not giving them more money and oil
.. Yemen recently...). All these factors are more than enough to limit the Saudi influence in the region because people no more accept to be in the same side with Saudi Arabia, and I'm not surprised that thousand of Arabs wants the entire country to fail !
At the end, those who sided with Iran against the interest of their country will discover the real face of Iran. There is a common saying in Arabic says that " اذا كان لك عند الكلب حاجة قول له يا سيدي ". That's what Iran is doing now with Arabs.
Anyway, I don't expect the region to go back as it was before the Arab spring. As long as Arab leaders are working for foreign agenda, people aren't building their relations with each other, there will be no end for the mess.
The big loser will be Arabs. Their countries will be converted into poor states below the standards of 3rd world, then it will be ruled by foreign powers like bananas.