People need to stop saying this. It's nonsense. Or maybe keep saying it so we know your clueless about how anything works that your commenting on
Why? (Honest question.)
https://blog.twitter.com/engineering/en_us/topics/infrastruc...
> Unfortunately, Haplo has its limits. Since we try to pull every single Tweet ID in a conversation every time a conversation is loaded in real-time, this is potentially an unbounded amount of data. We’ve found that if our platform tries to load more than a certain number of entries from our cache at once, our cache request latency will spike, and we begin to time-out on a significant fraction of read requests. Because of this, there is a limit of thousands of Tweets per conversation tree in this cache.
even just showing an ad is a ton work has a bunch of services involved
https://blog.twitter.com/engineering/en_us/topics/infrastruc...
Other stuff that I think explains the complexity
https://blog.twitter.com/engineering/en_us/topics/insights/2...
https://blog.twitter.com/engineering/en_us/topics/insights/2...
https://blog.twitter.com/engineering/en_us/topics/insights/2...
there's no single algorithm, its a bunch of parts coming together from hundreds of engineers and multiple services.
So, it can go either way and can be argued either way.