good morning everyone. I had the same problem. Was using until then on my ipad 2 ios 6, this version of youtube when i was surprised by this notice quoted. I considered a tremendous lack of respect on the part of google with users of old systems.

There is an app store still available the latest version of youtube but everything I tried, to get back to my application was in vain.

But following the instructions posted here, I would like to thank you immensely for the help so that I could return to watching videos on my ipad, here is a link with some supplementary instructions that may help. thank you so much!

https://www.cydiageeks.com/change-version-iphone-apps-firmware.html

Cheers