There are well-defined standards for how the role of every element is determined, and according to those standards, adding an onclick handler does not change th

There are well-defined standards for how the role of every element is determined, and according to those standards, adding an onclick handler does not change the role. Screen readers also don't access the DOM directly, there's an extra abstraction layer. Browsers expose accessibility data to the appropriate OS API, and screen readers use the data exposed by the OS. There's too much variation as-is between different screen readers to be piling browser-specific behavior on top.