Newer versions of YouTube require newer iOS updates that older devices (like the iPhone 5 or 6) can’t run. Performance:
For users on older iOS versions or devices, consider updating to the latest iOS version if possible. This often allows access to a broader range of apps and ensures the device benefits from the latest security patches.
A prompt will ask if you want to "Download an older version of this app." Tap Mobile Web Browser (Recommended) m.youtube.com
: You must have downloaded YouTube at least once in the past on any device using your current Apple ID. Steps : Open the App Store on your iOS 12.5.7 device. Go to your Purchased list (tap your profile icon). Search for "YouTube" and tap the cloud download icon.