I feel like developing an app for iOS is harder than developing one for Android.

Everything from writing code to building and publishing is overcomplicated.

I've done both, and this was not my experience. Nowadays, they're much more similar than different, but 10 years or so ago, "easy" was defined by if you knew Java or Objective-C. Android, like most Java, required a lot of code to do simple things (public static void main...), and tons of XML to make the app support so many devices. Objective-C had good boiler plate thanks to Apple and NeXT before it using the frameworks for years.

Now, SwiftUI and Compose are effectively cousins, as are Kotlin and Swift. Both App Stores have their quirks. Publishing is part of both workflows. It's really not harder for one or the other, it's just administrivia.

Unless you try to support wide range of devices. That's where android development is harder.