I agree this is an issue that needs to be addressed ASAP. But this may be a Youtube issue.
The apps are created by 3rd party companies such as Google in the case of Youtube. This issue is limited to Youtube so it may be caused by a Youtube app update and unrelated to Roku OS. I am just guessing here but this may be why Roku hasn't found a solution yet.
Not my problem. Roku individually authorizes the apps on it's "walled garden" platform which means they need to take responsibility for any malfunctions that occur. I'm aware of the situation going on between Roku and Google and I'm not going to be put in the middle of it. The TV plays other 4K content so TCL is not to blame.
The bottom line is, this TV came preloaded and advertised with 4K YouTube when I bought it. Roku cannot just push an update and remove that feature that I paid for and was previously working. If Roku cannot get it's app partners to fix their apps then Roku needs to compensate the users for loss of functionality. The contract is between Roku & Google, not the user and Google. Roku needs to address the problem STAT or provide users a way to downgrade to the previous software that worked.
I'm not at all convinced it's actually Google's problem. The problem appeared with the Roku OS 10.5.0 update.
I tried the COSTA RICA IN 4K 60fps HDR (ULTRA HD) on my 2 Westinghouse TVs and the video did not buffer. You don't need gigabit speed internet for HDR 10. All of my devices are connected via wireless. If HDR 10 was buffering on my TVs the blame would be on YouTube.
Regardless every single TCL 4K tv has this issue! Wether or not its the Youtube App broken on the latest update or the TV its a TCL Issue! To my knowledge no other manufacturer has this problem. @ektoplasm has explained numerous times in depth and great detail what the issue is yet we continue to get the same response. How about a solution to the problem?? Roll out a update that fixes it!