This comment is inappropriate - but since you are new to the forum, I will not report it.
Israel did not have the freedom of operation over Syria than it has now. What ever you think of what Syria had, Israel felt it was of military value so much that they destroyed it when given the chance. The equipment was not destroyed because it was ineffective to the extent that you say it was, it was destroyed because it was not manned at all. Could C130s, Refuellers have operated freely over Syria had Syria maintained its air defences. The answer is no.
Highly unlikely given that right now, there are no fast jets pilots in Syria right now. Any that were fast jet pilots have all lost their flight ratings of jets already and will age out before given the opportunity to fly new platforms. If there are Kaans operating over Syria, it will be staffed/manned by Syrian pilots. It takes more than 5 years to take a graduate to a fast jet pilot that can operationally man a fast jet platform and be effective in that role.
The Syrian Airforce decided to abandon their posts go home. In doing so, everything was destroyed. Yes, the equipment was old, but still far better than what they have now. Many militaries still operate the same equipment that Syria had before it was all destroyed. Not many people on this forum will agree with your assessments of the state of the military or their capability before it was destroyed.
Yes, Syria will sign onto the Abraham accords, but it wont get the Golan Heights back from doing that. Syria will have to give up that land permanently.