If the Turks managed to retain the rest of their OTL territory then yes, however with a far greater loss in WWI and a devastating loss to the Greeks in the independance war we could very well see Anatolian Turkey sliced up into British and French concession zones, along with the Armenians getting their 'historical claim' as they try to take advantage of the situation. If Istanbul ended up a city state as a result of the Turks losing badly, then I'd also envision the Greeks also getting much of the territory they imagined when they dreamed up their whole 'Megali Idea'.
Yes, what is left of Turkey would be turned to a Soviet client, but in order to get back Istanbul they'd have to cross the straits through a narrow gap while the Greeks, with additional territory in Western Anatolia, would be in a better position IMO.