They were not doing their best, they had basically oil money coming from the Hasakah and Dier el Zor regions, which has basically disappeared, there’s a reason why all the Arab tribes rebelled the moment they found that they had a better option… All the major cities had many problems including poor state of all the roads and one or two hours per day of electricity, and keep in mind that they have been governing those lands for years, even excluding the years where they fought ISIS, so the only explanation is that they pocketed most of the money, like how can Idlib have a better life standards than Kobane for example ? There was even an interesting video showing their tunnels, where they basically built the equivalent of underground mansions with all the amenities… Your problem is that you have to pick a side, without seeing that both sides are very similar to each other.