Maybe you can consider that on HN you are talking to experts who in their lives experienced dozens different UI paradigms and frameworks including deep experience with React, its ecosystem, its benefits and its warts. I am pointing out that the problem of "how can I scale this UI" is experienced by a very small percentage of apps. For Meta or Uber it makes sense as they need to coordinate overlapping real-time feeds where dependency graph is insane; why should however most apps bother jumping on this paradigm? There are complex yet performant apps like draw.io that never touched anything reactive and aren't missing it in the slightest.