It’s an odd claim, because people have been asking for this (nested routes) more-or-less since Next was first released. In fact, Remix is basically a compiler for the patterns we could achieve back in the days of React Router 2 and 3 (2015-2017).
The fact that the APIs looks similar seems largely inevitable based on the fact that everyone seems to be converging around defining routes using folder and file name conventions.
It reminds me of patent trolls who patent obvious software designs. I was looking for such feature long before I heard of Remix. I know he's the react-router guy, but nested views isn't exactly some novel idea - sites have been using it forever.
The fact that the APIs looks similar seems largely inevitable based on the fact that everyone seems to be converging around defining routes using folder and file name conventions.