Saudi Arabia is intensively policed for political opposition. Only communist China has a higher percentage of its population dedicated to spying on the rest of the population. The Kingdom of Saudi Arabia is an absolute dictatorship.
Saudis are used to keeping their finger in the wind, for any shift in public policy, and falling over themselves in a rush to swear what a great idea it is.
The main Islamist hardline preachers have already been arrested, and are facing potential death sentences - even highly popular figures with millions of (former) social media followers.
So officially, public opinion will fall right into line. My sense is that the huge (disproportionally) younger parts of the population are really yearning for modernization, social liberalization, and International openness. They would be amenable to welcoming this deal. A hard core of die hard Wahabbis will probably present a serious assassination risk, for a long time to come.
The ultra hard core are simply dying out.
There now in control of family business and the Saudi industries, men who are the sons and nephews and perhaps grand sons of founders who are in fact American educated. I have met several who came here and received college educations. They shun the sinful large state universities and attend smaller universities.
They are Saudi and they are Muslim but they are not fanatics.
Some time back, I met a young Saudi electrical engineer who was real and knew his stuff. In the past, Saudi’s had degrees but were not really very good and didn’t like to work. He held his own amidst the Indian and Americans. He worked for a very large American company with extensive facilities in their Saudi office