. Even if you manage to sideload an older IPA, Google’s servers often block these versions, resulting in "Error Loading" or "Update Required" messages. Methods to Get YouTube on iOS 9.3.5 The "Purchased" Tab Method
(available via Cydia for jailbroken devices) can sometimes restore functionality to old versions of the official app. App Store Version History youtube ipa for ios 935 exclusive
However, staying on an old operating system has a cost: the App Store stops working for many apps, or developers push updates that require iOS 15 or higher. Google’s servers often block these versions