[jscholes]

> Or potentially aria-role="presentation"

There is no such attribute as "aria-role", only the single word "role".

> aria-hidden="true" will make the element completely invisible to the screen reader software, whereas setting role will tell the screen reader "hey there is something here but it's job is purely aesthetic", and then the screen reader can determine what it wants to do with it.

This is accurate, but you should also ask yourself about design intent if you have the knowledge to do so (or can consult with someone who does). If you have decided that something should be hidden from a screen reader user, and have verified that your intentions are correct, aria-hidden is the way to go. Many accessibility bugs are caused by people using something like role="presentation" because they wanted to leave it up to the browser and/or screen reader to make a decision. The problem is, those software decisions are often wrong and inconsistent, leading to support requests and hard-to-track-down bugs.

Note: the above applies across the board, not just to images. The correct way to mark an image as decorative is via alt="" on the img, and you should be careful applying aria-hidden to anything as it can be extremely destructive. No ARIA is better than bad ARIA.