Many centuries ago people used to build their buildings utilizing the materials available in their own land. Few decades ago, people have started to import materials from other countries in order to build their own buildings.
I don't think the similarity of building materials is the reason why modern buildings look alike.
This change of building materials has impacted in many people's opinion and views. Travelers who visit different cities around the world today found that famous buildings are similar to each other as if they have visited this city before.
The prompt asks for your opinion, so you had better state it clearly in the introduction. Also, in the second body paragraph, you just mentioned what other people may think about the issue. Instead, I think you should focus on your opinion whether the trend is positive or negative
Dubai has moved to construct their buildings
In Dubai, buildings are constructed