Good point! I believe none of the other Edge platforms are fully open source yet (I don't mean their runtime being OSS, but the Edge Platform itself). Clouflare Workers is the only one that gets there half way with Workerd (they are missing KV, other APIs and the glue-code).
Right now the Wasmer Edge product usage is not in a stable enough point to make it open-source. I'd love to share the timelines, but anything that I say now will likely be wrong (as we are still iterating hard on the product).
> I would be interested in restricting specific requests to certain regions
I can see this being an issue if you plug the workload with data that is located in a specific region (for example, via a DB connection or doing API calls to an API in a specific region). Is that your use case?