That 3-step remove/reboot/reinstall is a common step to resolve issues, but it doesn't always work. There's something else going on.
I re-read your post, and I have a question about your wording. I read it one way, but I see it can be read another way. I want to ensure I understand the issue.
YouTube isn't showing videos I need. ...
I read that to read that YouTube wasn't showing any videos. But, it could be read that it isn't showing certain videos. So, which is the issue?
Does the YouTube app launch?
Are you signed in to the YouTube app?
Do you see any videos listed? Any at all, not asking about certain videos. Do you see any listed?
Will any videos play?
Do you see the videos you're after on another platform, such as a mobile phone YouTube app, or at https://youtube.com/ ?
Roku Community Streaming Expert
Note: I am not a Roku employee.
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