I think the sense which the original article talks about is an important one: You can generally use vanilla libraries for non-UI stuff. You don't generally need to use anything React specific.
This is in contrast to frameworks like Angular which try to reinvent to entire ecosystem in an "Angular style". Which is a massive pain if the Angular version has a bug, doesn't implement the feature you need, or is simply far too complicated because it's trying to be everything to everyone. In React, there are usually 2 or 3 options for everything with different trade-offs. And this is amazing, because you can pick the library that works for your project.
This is in contrast to frameworks like Angular which try to reinvent to entire ecosystem in an "Angular style". Which is a massive pain if the Angular version has a bug, doesn't implement the feature you need, or is simply far too complicated because it's trying to be everything to everyone. In React, there are usually 2 or 3 options for everything with different trade-offs. And this is amazing, because you can pick the library that works for your project.