Incorrectly configured relevant settings on your iPhone X, such as network-related parameters, may potentially influence the YouTube app in some manner. If the app began to crash after you made changes to your iPhone settings, try reverting the modifications and seeing if it makes a difference. If not, you may alternatively reset all of your iPhone's settings. Here's how you do it:

1. From the Home screen, choose Settings.
2. Select General.
3. Reset may be found by scrolling down and tapping it.
4. Choose Reset All Settings from the drop-down menu. This will restore your iPhone's settings to their original state while leaving your data intact. As a consequence, no data is lost.
5. Select the option to Reset all network settings to reset all settings on your iPhone X.
6. Enter the right passcode for your device if required.
7. Then, to confirm the reset, press the choice.