Inclusive Web Performance Metrics for Assistive Technologies

Scott Jehl writing about getting beyond visual-rendering markers, like first contentful paints, for web performance metrics:

These metrics are often touted as measures of usability or meaning, but they are not necessarily meaningful for everyone. In particular, users relying on assistive technology (such as a screenreader) may not perceive steps in the page loading process until after the DOM is complete, or even later depending on how JavaScript may block that process.

Absolutely. Metrics undoubtedly drive how performance is tuned for off-the-shelf frameworks, and not just the sites that use them. Including assistive technology in those metrics is long past due.