It would be great if Astra theme, popular as it is, had the accessibility-ready tag on WordPress.org. According to this thread (https://wordpress.org/support/topic/astra-accessibility-ready-tag-removed/) they did have it at one point, but the tag was removed until the final review. That was most of 3 years ago, and I have not been able to find out if the theme was resubmitted for the accessibility review.

The funny thing is that on Astra's site they say:

Astra is accessible and follows WCAG 2.0 standards. It meets the AA level which is essential for usability.

It would be nice to see the evidence behind that claim.