I use YouTube on almost a daily basis. I'm usually on my Ultra 4800, and have never encountered a problem. I recognize that some users are having issues. But it's not system-wide, which makes it extremely difficult to troubleshoot. And with misbehaving applications, the first step is always to remove, reboot and reinstall the app. Unfortunately, that can't be done with the YouTube TV channel, as once it's removed it can't be added back.
There is another way to accomplish the same thing without losing any installed channels, but it's more time consuming. A hard factory reset will wipe the device, and then when it's set back up to the same Roku user account all the existing channels will be restored, including YouTube TV if it's there previously. One would still have to reenter user credentials on the channels that need it, but it is one way to "remove/install" a misbehaving channel. And with any computer program, sometimes something gets corrupted in the code and a clean install is the only remedy.
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