The difference is not what you write, but what ends up in your user's DOM. You can still use custom components in your static site generator or in your backend

The difference is not what you write, but what ends up in your user's DOM. You can still use custom components in your static site generator or in your backend code. Abstract it however you want. You could use React Server Components with whatever component and interface you'd like. But the result in the SSRed or SSGed DOM should be the one from the article.