I personally own a Mac mini specifically for this task. When it comes to compiling the developed app however you WILL need Xcode because it’s required to digitally sign the developed app and to upload it to the App Store as well. Now if your question is “can I develop using Xcode or Obj C “ in windows 10 then that answer is sadly no but considering the OP asked of they could develop iOS apps on windows then there is nothing stopping them from create a utility app or even the next big game on the market. This particular technology has been around probably longer then some of you “developers” in here apparently There are also non native apps that use web view to create hybrid applications that are built specifically with web languages but utilize api that allow you to interact with devices api such as vibrate, contacts, phone calls etc. With that said you could also (which I do regularly ) use Kotlin and create a multi platform application (design and develop once across all platforms) right inside of android studio on windows 10 and now windows 11 (for testing at the moment) net (c#) and while it’s not obj c it would still be native. Now, with that says just like most alternatives it uses Xarmarin and you would develop using. Visual Studio 20 both support IOS App development.
You can absolutely develop IOS apps on windows 10, Windows 11. I’m confused, what is everyone talking about.