iCloud sync is a helpful feature not just for Apple's first-party apps, but also third-party alternatives available in the App Store. However, it appears that there has been a lingering issue causing many third-party apps to run into issues with iCloud sync. Which is leading many app users to point the finger in the wrong direction as Apple remains quiet on the subject.
Many developers unhappy with apparent iCloud syncing issues in their apps, leading some to disable the feature altogether