This appears to be a security problem at Google's end. It has been reported that if one goes into one's Google account and attends to the suggestions in the Google Privacy Checkup, videos will again play in YouTube.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well. If this post solves your problem please help others find this answer by clicking "Accept as Solution.".
Streaming Stick 4K+ 3821 | Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X
Already did the google privacy settings things, it showed no issues, all devices were allowed, still no videos playing on youtube. I have a hunch it may have something to do with their ad system. Hopefully Roku and google can work on this to get it fixed quickly.