So can we assume that the issue has been solved with update "to iOS or iPadOS 13.6.1 or later" (cf.
https://support.apple.com/en-us/HT211686) or are people still having trouble?
How about those iPhones then that can only run iOS 12 and experience a similar system storage problem (like my old iPhone 5s, 12.4.9)? Is Apple in the link mentioned above describe a specific problem of iOS 13 ("If you have iOS or iPadOS 13" or is it basically the same issue many of us have been experiencing starting years ago (with iOS 12 and iPadOS 12 or even before?)
In other words, for those still on iOS 12.4.9, do you think there is no way to solve the problem without an update (which is not possible), or is there a different cause in iOS 12?
And if I get a new iPhone SE 2020 (which I am considering) and migrate my date from my old iPhone 5s, 12.4.9, will the issue likely disappear?