The Subscriptions feed error message is resolved for almost everyone. If you're still seeing it, know that it will be fixed soon – thanks for your continued patience! You can follow along here for any additional updates: https://yt.be/help/CBxM https://twitter.com/TeamYouTube/status/1119013035580878848 …
Appreciate your suggestions! We're working on adding more features to YouTube. You can always share them by sending us a feedback report: https://yt.be/help/a4gp . It'll help us prioritize your request.