Why should you bin it?
I have iPhone 4S iOS 9.3.6, iPhone 6 12.4.6, iPhone SE iOS 13.4.1, iPhone 8 iOS 13.4.1 and an iPad Pro iPadOS 13.4.1. Prior to that I had iPhone 3GS which is not working any more.
I have been updating all these devices whenever a new iOS is released. I have never encountered any issue whatsoever after any update because I have never downloaded anything over internet directly. Always used apps from App Store only.
Though iOS is not released for many of the above devices but I do not find any issue in its functionality.
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