Whatever you say or hope, you will have to deal with neighbour Yemen which you bombed to hell and they will become 150 million people in a devestated country, looking for food, just like Syria being the neighboor of Turkey.
I don't think Jennifer Lopez shaking it in land of Islam and Nabi (a.s) will be a long term solution for your saudi regime (named after a tribe).
Yemen is independent from Iran and their independent policy will continue, Saudi Arabia could only change that by winning against them through war (good luck). Even if Islamic republic disappears, Yemen and its policy will continue.
At least we didnt bomb Afghanistan or Tajikistan to hell, so our responsibility towards them is less heavy. If they want al-qaida like government they can have it, after 40 years new generations reject it. So saudi gains are very short.
Good that you follow Arab demographics. This way you will know already that the era of opportunistic meddling of foreigners in unstable/war-torn Arab countries won't end well. US experienced this in Iraq not long ago. You experienced it in Syria just a few weeks ago after losing 6000 Iranians and 50 + billion USD.
Yemenis as a people are closer to Saudi Arabians than any other people, along with Omanis. We never had any major wars or problems but mostly always lived in peace until the Houthi cult (30 + year old cult) emerged. Just like millions of Yemenis live peacefully alongside us.
Nobody bombs anyone other than Houthi terrorists and a few, unfortunate, collateral damage as in any war, because the Houthis hide among civilians, hospitals and what not. There are many videos that confirm this online.
No systematic killings either. That is not how we operate. We leave indiscriminate barrel bombings to the Iranian regime and its allies.
You see, KSA locked up and dealt with its minority of vocal and influential extremists/fundamentalists that interpreted Islam in a restrictive, wrong and harmful way for the people and country. Now for the past 7-8 years KSA has returned to normalcy as prior to 1979. This is why entertainment, music, world class international sporting events from MMA, boxing, football, Formula 1, tennis, e-sports (list is long) is being hosted with widespread popular support. This is why you can now find women wearing niqab's next to women not wearing headscarfs. Each minding their own business while being respectful and dressing respectfully. Enjoying the same entertainment from watching football, music, art, tourist attractions or whatever. Like in any other normal Muslim country. Like it always was the case.
KSA now has more women working in the workforce than most countries of the region. One of the most educated populations as well. Nobody accepts being hijacked by a few dinosaurs any longer. From the ruler (MbS) to the average people, of which 2/3 are under 30.
This is the same, I believe, everywhere in the Arab and Muslim world. Most people do not accept extremists hijacking their countries and lives.
No, they won't because no sane educated Yemeni in Northern Yemen looks at the incompetent Houthi terrorist cult as people to emulate or their incompetent rule that has given Yemen nothing but misery. Unfortunately an entire generation that has not known anything else has been born but eventually they will notice and see what other parts of Yemen (in development) looks like and they will demand the same. As well as the technological development of the world will make people question such failed regimes. Similarly as what is happening in Iran right now. A non-religious young Iranian, I do not believe that he is very supportive of the Iranian Mullah's wasting 50+ billions of dollars on failed projects in the Arab and Muslim world.
What gains? KSA places no importance on tiny Tajikistan or Afghanistan geopolitically. We have no hostility to Tajiks or Afghans (many live in KSA) and most of them look favorable at KSA and Arabs. Many historic and cultural ties as well for well-known reasons. Same majority sect (Sunni Islam) and overall understanding.
As for whether Afghans want to be ruled by Taliban as currently and before or Tajiks want to be ruled by communist dictators (as for the past 30 years) this is as always up to them and none of my business.
Unlike the Iranian regime, we don't want to force failed regimes/terrorist groups upon anyone. At most we voice our opinions on regime x or y, as I have done with the failed and murderous Al-Assad regime, but nobody imposed themselves on Syrias even when he was around.
On the contrary, the pragmatic MbS invited him back to the Arab League and normalized ties, not out of love for the Al-Assad regime, but for the sake of Syria and Syrians and to help them end their political and economic isolation.
As a final statement, having met several Iranians in Makkah, Madinah and in GCC states and in the West, Arabs and Iranians (regular people, especially neighboring Arabs), have no reason for any hostilities.
The only problem (main one) in our recent relationship has been your Mullah regime. As everyone is well aware of, including most non pro-Mullah Iranians.
For instance, I just watched the arguably most famous Iranian foodie on Youtube (Mister Taster) food tour in KSA. Not to my surprise (actually) his most viewed video is from KSA.
And from what I could see and his comments during the videos, there were many similarities just in food alone.
Anyway we are off topic, so ending it here.
Just a final advice, tell your Mullah regime to stop this destructive and opportunistic meddling in war-torn/unstable Arab countries. You just saw how such projects end (Syria). Similarly will be the case with Northern Yemen (Houthis). Mark my words.