If I have a VM with an external IP in say region us-east1-*, that reads data from a multi-region US bucket, would that be free or count towards "Download Worldwide Destinations"?
Google doc seem to suggest it's free, but on the other hand this medium post seem to suggest otherwise.
Based on the documentation you quoted, it is still free. However it was announced on this article, that there would be an upcoming pricing changes for Cloud Storage and it would no longer be free starting October 1, 2022.
Reading data in a Cloud Storage bucket located in a multi-region from a Google Cloud service located in a region on the same continent will no longer be free; instead, such moves will be priced the same as general data moves between different locations on the same continent.
Additionally to help you estimate costs, you can use the GCP Pricing calculator where you can specify parameters such as the Egress type, Storage class, etc.
