Yes, it's easy to build entire cities from scratch in a centrally managed society, such as a dictatorship or communist nations.

It's also easy to have cities grow fast, if you're primarily a rural/agrarian nation, and suddenly have a transition to become urban. This was (for example) Canada in the 1900s. Mostly rural, yet now it's mostly urban.

Canada saw fast growth of cities back then.

It's maintaining large cities once the fast growth is over, that is a different story. How will, for example, China look in 50+ years? 100+ years? When all its newly built mega-city projects are crumbling.

> Canada saw fast growth of cities back then.

It still does—Vancouver and Calgary have both almost doubled in population over the past 30 years [0] [1].

[0]: https://en.wikipedia.org/wiki/Greater_Vancouver#Demographics

[1]: https://en.wikipedia.org/wiki/Demographics_of_Calgary#Civic_...

> Yes, it's easy to build entire cities from scratch in a centrally managed society, such as a dictatorship or communist nations.

This is generally true, but Indonesia is neither