> What a ridiculous point. AWS achieves non-trivial things at scale all the time, and brag about it too.

Many companies achieve non-trivial things at scale. Pretty much every good engineer I speak to will list out all the incredibly challenging thing they did. And follow it up with "however, this component in Billing is 100x more difficult than that!"

I've worked in Billing and I'd say a huge number of issues come from the business logic. When you add a feature after-the-fact, you'll find a lot of technical and business blockers that prevent you doing the most obvious path. I strongly suspect AWS realised they passed this point of no return some time ago and now the effort to implement it vastly outweighs any return they'd ever hope to see.

And, let's be honest, there will be no possible implementation of this that will satisfy even a significant minority of the people demanding this feature. Everyone things they're saying the same thing but the second you dig into the detail and the use-case, everyone will expect something slightly (but critically) different.