Excellent question that I have as well.

I have encountered the exact same problem with my apps that use iCloud, and no help from Apple at all. I think the only thing we can do at the moment is to spread awareness about this to slowly grow the pressure. I have written an article on medium.com with the title "Why iOS Developers Should Never Use iCloud in Their Apps" that summarises the issue: georg.howen.de/why-ios-developers-should-never-use-icloud-in-their-apps-65aa303e4052. Feel free to share it on social media and professional networks to reach as many fellow devs as possible. Maybe this helps to prevent more damage and maybe lead to a fix sometime in the future.