A so-called CAPTCHA is a little "puzzle" or "task" people has to solve, before they are allowed to do things on some websites, like signing up.
Often these puzzle requires the user to do a task, that is not easy, or maybe even impossible, for some people. For example people with poor sight and blind people.
The above post was meant as a suggestion, for the DuckDuckGo team, on how they can make their website, more accessible / "better" to blind people.
It is not something you, as a general user of DuckDuckGo, should to be worried about. : ) It does not affect your use of DuckDuckGo. : )
It was just a technical tip for the site admin on DDG.
I hope this makes sense. Sorry, for the confusion! : )