What’s the syntactic sugar feature here? Top-level await is part of the language spec.

One into which you have to opt in, yet.

I don’t think that’s true. It’s supported in any ESM module, per the ESM standard, without any config or runtime flags. If you mean using ESM to be the opt-in mechanism, that’s not a meaningful distinction. CJS modules and require have always been synchronous and likely always will be. Changing that would break too many things.