Hi Richard Cheung1,
Thank you for reaching Microsoft Community. We appreciate for sharing your concern to us.
Could you verify the browser you're using to access YouTube TV?
The Surface Pro X comes with an ARM-base processor. To operate YouTube TV on Arm devices, there may be a limitation or compatibility issue. To confirm this, you may get in touch with the app developer to check if the said application works on an ARM device. To learn more about ARM-base device, see ARM-based Surface devices FAQ - Surface | Microsoft Learn.
Kind regards,
Lavenia