Remix 3 is a continuation of the Remix framework that abandons React and is more experimental. The old remix did indeed "work itself out of a job" by simplifying all of its features down until it became version 7 of the react-router library

IMO it's an amazing story. Remix was once a paid framework that focused on "using the platform". Then they open sourced it. Then they realized all of their work could be reduced to some new features of the popular react-router library.

They're basically the exact opposite of Nextjs which has a reputation of advertising framework features that are actually more like Vercel features. Though I acknowledge nextjs has been making a lot of progress on reducing their "soft lock-in"