'aria-hidden' can be used to hide visibly rendered content from assistive technologies.
If an editor wants to hide content from all users, we recommend using the HTML5 ‘hidden’ attribute (along with CSS 'display: none' for browsers that do not yet support 'hidden').
When can aria-hidden be used?
It is appropriate to use 'aria-hidden' if hiding this content is intended to improve the experience for users of assistive technologies by removing redundant content.
<p aria-hidden="true">This content is hidden.</p>
<p aria-hidden="false">This content is not hidden.</p>
Siteimprove flag aria-hidden based on this premise that the HTML5 ‘hidden’ attribute is the correct way to hide elements, and ‘aria-hidden’ could be either true or false based on its use.