But now you have to know which bucket the file is in, have the AWS CLI tools installed, use Terminal, copy the URL to messages / email, etc.

How is this easier than "right-click, pick a menu option"?

(If I want an expiring Dropbox link, it's there under 'link settings' in the pop-up. Admittedly only has date granularity but still there as an option.)

Example from the console: "Setting up an Amazon S3 bucket to share files"

https://gist.github.com/pjkelly/be2cd3881e766620a411

Again, how is this easier than a single right-click in Finder? Also don't those files need to be public to create a link? You can't create a link to a non-public file which grants access either directly via the link or with a password?

...are we deliberately reenacting the original Dropbox thread here?

It usually ends up happening when the Dropbox thread comes up, it’s really interesting seeing both sides rehash the same points.