Disclosure: I used to work on the Xbox Live team at MSFT but no longer do.
I had the YouTube app crash on my Xbox One just yesterday. I hit menu and selected quit. Waited a few seconds. Hit menu again and quit wasn't an available option which should mean that it's done being force quit. Started YouTube again and it will still hung playing audio with a frozen picture. Sometimes I'll start it again and it'll just show the YouTube logo for a few seconds then return to home. It'll often do this a few times in a row. I have maybe 6 people in my neighborhood with Xbox Ones that all experience the same issues.
On the other hand, if you don't hit quit, than hitting home and opening a bunch of other apps is exactly what you'd have to do to get the constrained (minimized) app to force quit while in the background.
I had the YouTube app crash on my Xbox One just yesterday. I hit menu and selected quit. Waited a few seconds. Hit menu again and quit wasn't an available option which should mean that it's done being force quit. Started YouTube again and it will still hung playing audio with a frozen picture. Sometimes I'll start it again and it'll just show the YouTube logo for a few seconds then return to home. It'll often do this a few times in a row. I have maybe 6 people in my neighborhood with Xbox Ones that all experience the same issues."
And it was just confirmed by another HN user.
For example, when your YouTube app crashes/hangs on the Xbox One, returning to the menu does nothing as the app pauses/runs in the background. You can hit the menu button (akin to a right-click) on the YouTube icon and select Quit. If you run YouTube again, it'll still be running and crashed. The trick is to menu button and quit YouTube and then run a couple other video apps (usually Netflix and Hulu do the trick). This is usually enough to fully offload the YouTube process and allow it to run again.
This is how Microsoft's flagship entertainment console works. In 2016. Seriously.
Everytime our cat sitter watches our place, I have the Xbox 360 hooked up for her to watch videos on. It's easier to use and more reliable.