I think most of it is very easy to implement in Nostr but the real layer which is missing is a way for machine learning to pick which notes to display based on user activity and engagement. That’s buildable and a lot easier/cheaper than it was when TikTok or even IG reels were developed. But we have no way to bundle up user engagement data and send it to a trusted algorithm service. We could do a DVM or custom relay to display the content based on the algorithm service. 

The other issue to address is that TikTok and its clones are very optimized for performance with incredible low latency uptime. You need a good CDN and really optimized clients.