That’s not true. Apple has strict requirements of how an app should work in touch before it’s even approved on the App Store.It's really not weird though, If they add mouse support to iOS then what happens is instead of app developers focusing on making a great experience for a touch input device they start to think about how to best utilize both options and then the potential to just port over your app that ends up working much better with a pointer than touch input becomes a reality and the need to innovate great apps for the iPad potentially starts to slip away.
Also, Apple is already planning for cross platform iOS and macOS apps this coming year. They will have mouse support already, so it only makes sense.