Their rational was pretty solid in the PR, but seems they overestimated how ready the community is to embrace newer best practices and they are back tracking.
What are they, in plain terms? Is it just manually hoisting what you know a route needs all the way to the top of the tree? Or is it some compile time magic that analyzes your components used, making the decision for you on what to fetch for a route?
And Meta's way of doing this is with Relay, so you are still defining component data requirements with the components and query fragments, but there's a compile step that produces those route level queries.. so you still get "co-location of a component's data requirements with the component", and "top level early data fetch" for the render-as-you-fetch pattern.
This change breaks the fetch-as-you-render pattern where components make individual data requests for their data, because that pattern is considered bad for performance (for Meta's use case).
Essentially data fetching starts as soon as possible. Right after routing, right before rendering.
The fact that the suspense change made it this far shows how the react team has lost focus. Now more than ever, the ecosystem is really primed for a competing framework to dethrone react. I say this as someone that has invested a lot into using react.
Preact is how I wish React would have evolved: stay small, keep a simple interface, focused on being a view library instead of a sprawling framework.
Kind of discredits all your opinions on that topic