For any tenant
http://stream.office.com/ front page has not ever showed ALL the videos, only the ones i have uploaded or opened - this front page is totally useless if it does not show all the videos that are saved to the sp platfrom (sharepoint search can show all the videos in the tenant if i have permissions). This is not answering to your question but yes, we are experiencing problems that obnly few videos are listed in the "all" section