If Turkiye designs to capture Manbij then Turkiye will capture Manbij. It may be very very expensive but Erdogan will not lose face by failing to take Manbij once he has undertaken the project. The Turkish army is large enough to sacrifice many soldiers in the attempt. Turkiye can either decide not to assault Manbij or it can be deterred by the United States. Russia may not be able to keep it from happening. Whatever rapprochement seems to be occurring between Russia and the Turks is totally superficial. The Russian Turkish enmity has endured for centuries. Moscow has always seen itself as heir to the Greek Empire and the Turks see it the same way.
Ultimately, yes that is reality.
I’m not sure Erdogan is living in the real world. His Ottoman Daydream is so real to him, he actually believe he is chosen to do it.
That is a very dangerous thing.
Kurds have no armor. However Syria has armor and aircraft. The Syrian Army is directly across Al-Bab from Turkish Army. The US support for some of Turkey’s terrorist allies has been stopped. So US will not fly air support, it is questionable if Russia will, SDF is now pretty strong and there is another element that could appear. Won’t mention that by name. It is better not to.