React is not large, is of moderate complexity (most of the complexity of "a React app" lives well outside of React itself), and can be stripped down to a fully static templating language without much effort. As I've linked elsewhere, I turned React into an email templating engine once because I don't like Handlebars; rendering JSX as static, no-JS HTML is a one-liner when you throw it a React component.
Using React for a static website is totally fine.
So is not using it.
Being weird about it is not fine.