Yes, and that's exactly the problem. It's like choosing a microservice architecture for resiliency and building all the services on top of the same database or message queue without underlying redundancy.
It is kinda cool that the worst aws outages are still within a single region and not global.
But I think what wasn't well considered was the async effect - If something is gone for 5 minutes, maybe it will be just fine, but when things are properly asynchronous, then the workflows that have piled up during that time becomes a problem in itself. Worst case, they turn into poison pills which then break the system again.