Question

Why was Mehmed II’s two month seize of Constantinople successful

Answer 1

One bad thing might be the extra taxes that non-Muslims would have to pay (the jizya) which was a part of Islamic state administration at the time. It was an extra burden placed on part of the population (as well as a source of income for the state in question). Another was the impact of no longer being Byzantines -- their empire was effectively ended and the survivors had to try and find a way to live under a completely new ruler. While that might not seem like much, imagine being part of an empire that had stood for more than a thousand years and then suddenly have it taken away. It was probably pretty traumatic for those in the city to live through that.

But one good thing was that Mehmed II was a tolerant ruler allowing non-Muslims to freely practice their faith within his empire. He also invited artists and scholars from outside of the Ottoman Empire to translate works and contribute to rebuilding the city of Constantinople into Istanbul. For the most part, if you stayed loyal to the Ottomans, you were left alone. Mehmed saw himself as the new Caesar and hoped to make the city the heart of a universal Islamic empire.