Having trees in urban places is a great idea. Trees helps in purifying the air as they absorb potentially harmful gasses and gives out more clean and fresher oxygen.

If there will be fruit bearing trees everywhere could be wonderful, yes there will be free fruits for everyone and hungry people will be lessen so that's a good thing. But sadly we live in a greedy world, chances are there will be some people who will grab all the fruits and sell them even they never planted a single tree. Fruit trees are also appealing to children's eyes. I was that same kid who climbed trees before lol. It's fun but also not safe.