My impression from the later responses was that they underestimated how often this particular pattern for parallel loading with React Suspense is used. The people that are slow to embrace the newer patterns would likely not have used Suspense at all, so nothing would have changed for them. This would have affected a specific subset of people that used Suspense for parallel loading, but didn't switch to route loaders.
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?
Haven't used them myself yet. As far as I understand it's essentially moving the data loading into the router. The router has an API for the loaders so the rest will work automatically like loading states. So yes, this means you have to define what to load at the top where you define the routes. Though I think this also works with nested routes, but I don't have any experience with them.
> So yes, this means you have to define what to load at the top where you define the routes.
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).
