not only Safari, several other apps such as Music (which also has several annoying quirks)
never understood why they did not get their own lifecycle if they have dedicated teams for each of those apps
My company keeps the testing cycle smaller by only adding new OS-dependent features to its mobile app when the minimum supported OS version gets incremented and a feature is supported in every supported OS version. That means that the iOS app is only now getting features that were added in iOS 15 in 2021.