The final official YouTube versions compatible with Android 5.0+ (API 21) were released in late 2021. While they may require "spoofing" to bypass the update screen, they are the most stable "official" experience.
: Follow the prompts to enter a phone number and receive a six-digit code via text or call. Google Help Common Issues on Android 5.1.1 Forced Updates app youtube android 511 verified
Do NOT download versions 18+. Those are built for Android 8.0+ and will immediately crash ( Parse error or App not installed ). The final official YouTube versions compatible with Android
For hands-on help with device updates or software troubleshooting, consider visiting these types of local businesses: Device Repair & Software Shops Google Help Common Issues on Android 5
Your best bet is:
The official YouTube app now generally requires at least Android 9.0. Lollipop Support:
If you still have a semi-functional app, you may need to manually accept new permissions in the Google Play Store under My apps & games to restore some features [2].