6 very important words.
And I'd add one more: taqiyya.
“if they are sincere about it.”
They have already imprisoned some high profile proponents of the more extreme views - guys with millions of followers.
Letting women drive is more than just superficial. It has special status in Saudi Arabia as a political litmus test of which side you are on, like abortion here.
So far, the new guy is moving much more strongly and convincingly than we have seen before from the Saudis, but their record is so bad that a lot of convincing will be needed. And he could well end up being reversed in a counter-reformation or coup. But there is strong indication that real change is afoot. Time will tell.