Exactly. It's "good enough" engineering. HTTP polling is guaranteed to work for every client, all of the time. While the other solutions mentioned offer improv

Exactly. It's "good enough" engineering. HTTP polling is guaranteed to work for every client, all of the time. While the other solutions mentioned offer improved performance with regard to latency and bandwidth, neither of those are going to noticeably improve the user experience. And having to deal with stuff like bloated libraries, broken websocket connections or browser incompatibility mean the proposed alternative solutions have a very real possibility of degrading the user experience. I get it, the author sells real-time solutions, but in this very specific use case, I think HTTP polling was actually the correct choice.