The Saudis are NOT backing or behind the Kurds in Syria and never had or have been, regardless of their own regime change agenda against Assad - which involved us backing the so-called “Free Syrian Army” and sitting and watching as the Saudis, Turkey and some Gulf states ALL funded Islamist groups against Assad, NOT the Kurds.
The Kurds were - in Syria - acting similar to, but also in opposition to ISIS, taking advantage of the destabilization of Syria to affect positive changes in their own interest.
While it is true that the Kurds have more than once been betrayed by the west, it is wrong to make-believe that the Kurds actions in Syria have more to do with “U.S.-Saudi” designs than what the Kurds themselves see in their own interest.
The US told them they'd be supported in their revolt against Sadaam after we whipped Sadaam in '91. That lasted right up until the Turks complained and made some base concessions. So, how'd that work out for them in Iraq?
The Kurds have been played for suckers by the US so many times they should wear 'Tootsie Roll Pop' patches on their uniforms. They don't care if the money to fund them comes from the Saudis or from Satan himself if they believe that this time it will be different and they can establish their own State.
You figure this time is different, fine, maybe so. Maybe not. We shall see.
The only people other than the Kurds who actually would like to see a Kurdish State are the Armenians and through them the Russians to the extent that it doesn't interfere with their Syrian arrangements.
IOW, to the extent that little if any of the land the Kurds have total control over is land important to Syria. Now, add to that mix the Orthodox Church in Russia pushing for Kurdish State to the West of Armenia and maybe something will work out. If it does, it'll be in spite of what the US and Saudis want, not because of what they want because it won't follow their blueprint that takes as little from Turkey as possible in hopes of salvaging Turkey as NATO's Southern flank.