You can use node to bundle react into a minified js bundle. But that’s typical for any complex js usage. My raw rails apps still have a node step to bundle a bunch of js libraries I need for the front end.
I honestly think the post is just incredibly naive and they haven’t ever needed more than basic rails templated html functionality in their frontend. They can’t see the value in a larger frontend framework because they don’t need it. They tried replacing the entire rails stack with a front end and didn’t understand why anyone would use that and found it painful to do the backend stuff.
Here’s the path for the og poster to grow. Add more and more complexity to the frontend. At some point you’ll want to use the node system to manage the front end js libraries you are using. At some point you’ll want something more consistent to manage the front end across the site. You’ll look to Vue or Angular or React. You add this to your rails app and now you have a very common rails+react stack.
It can’t see a justification for this post apart from naivety.