I'm using the Roku Ultra streaming device (actually 6) for the past year to stream YouTube TV. Recently, within last 3 days, shows that I've watched in their entirety in my library do not show as WATCHED as they did in the past. Shows that I have watched 1-2 times still show as not been watched.
Also, live shows and/or shows in my library that I do not watch all the way through to the end - use to show in the RESUME WATCHING and pickup from where you stopped. They no longer show up as Resume and there are shows there that will not go away even though the show has been watched.
I submitted to YouTube and they claim it's a Roku issue. I seriously doubt that but I'll post here and see if anyone else is having the same problem.
I seriously doubt it too.
In the first place, your viewing history has to be kept on YouTube's servers, not Roku's, so it will be accessible no matter how you access your YouTube account - computer, phone, various streaming devices.
YouTube supplies a version of their app to run on the Roku platform, but it's YouTube's app. It may be that YouTube's Roku implementation has a problem, but it's ultimately YouTube's problem to fix.