I've got notes/ideas from 2011 that revolve around building a personalized online TV station. YouTube leanback from 2010 was the first major attempt at that. Load it up, videos start playing. Though it looks like they've opted for the choose-your-thumbnail layout now.

Once we're able to nail recommendation algorithms such that near-100% of all suggested content is perfect and desired by that user, game over. Just show them a stream of content. Don't let them pick and choose or require scrolling. Would be like turning on the TV and just getting constant dopamine triggers with no downtime. Videos, photos, text, whatever, perfectly tuned to your desires in that moment.

Internet drugs.