Hello @Alleycat1284 and welcome to the Community. You can uninstall the YouTube app. Tap on your device/battery icon, then your Sense 2 tile. Tap on Gallery, then scroll down to your app list. Tap on YouTube Music to go to the app details. Tap on Uninstall.
I don't use it either. I don't think I would have tried, except to try and help you. Thanks for your question!
Laurie | Maryland
Sense 2, Luxe, Aria 2 | iOS | Mac OS
Take a look at the Fitbit help site for further assistance and information.