Because it's more interesting. These architects want to create an opus.

As a data point of one, I don't like complexity.

Often, complexity is the result of not really understanding the problem space well, which results in organic complexity as one solves the problems as they are discovered. React is a perfect example of this. You solve the happy-path of state management and all the non-happy-paths create additional complexity in the framework. But nobody actually questions why those edge cases exist in the first place and why it should really be "solved" or not.

I have noticed that most developers prefer to spend a month typing code without having to think hard, instead of thinking hard for a bit and then solving the problem in a day.

I don’t get it. It’s very strange.