Does Accessible Authentication apply to CAPTCHA?

In the proposed specification for accessible authentication, it notes that cognitive tasks can include:

solving of puzzles, which mathematical captcha are, and arguably ones which require that you visually work out which cells contain a certain object.
transcription, such as typing in characters -- which can you have to do as part of an audio captcha.

So would an authentification process involving a captcha would need an option which did not involve a cognitive test. I am partly raising this as I notice CAPTCHAs are much more common when you use autofilling.

At the same time, non-text content says "However, [captchas] are widely used, and the Web Content Accessibility Guidelines Working Group believes that if CAPTCHAs were forbidden outright, Web sites would choose not to conform to WCAG rather than abandon CAPTCHA."

w3c / wcag

Does Accessible Authentication apply to CAPTCHA? #1285