In particular there's a theme of JS being totally optional: "Rails 7 takes advantage of all of these advances to deliver a no-Node default approach to the front end – without sacrificing neither access to npm packages nor modern JavaScript in the process." "The same approach is taken with CSS bundlers that rely on Node. [...] If you’re willing to accept the complexity of a Node dependency, you can pre-configure your new Rails app to use any of them"
That seems like a smart goal. They're not trying to go it alone, but they're clearly trying to draw some boundaries that keep the JS chaos/complexity at the edges.