Hi bydigger,
Thank you for the question. As far as I’m concerned and from what I’ve studied about WCAG 2.1 level AA, there is nothing that affects the theme directly, actually. So, yes, the theme should be perfectly compliant with WCAG 2.1 level AA guidelines and I do not plan any update to my themes regarding this WCAG version.
But if you found any specific issue, please report it here so I can take a look and provide a fix.
Tip: For accessibility testing please check the knowledge base article.