This is an impeccable example of how a quote-only answer should not be written.
For the sake of context, quote-only answers aren't forbidden unlike link-only answers. But those are not preferred. As has been accentuated in the answers to this Meta SO post:
We prefer answers to be your own original work, contributing something new to this site specifically, not just copying something entirely from somewhere else. ... Note that even if you find the complete answer somewhere else that can be copied (with proper attribution), surely there is still something you can add on top of it ...
How does the quote apply? Does it directly engage with the question? Does it clear up a misconception underlying the question? Does it explain how to think about the problem? Something else? ... What are you trying to get at with this wording? How does the explanation apply to OP's circumstance?
Quote only answers are poor in the sense that even if those are self-evident, the poster ought to explain how a post of this kind helps OP's cause. Otherwise those would be prone to misinterpretation and dearth of communication would raise questions (as done here by whuber) all the more showing their lack of ability to construe a coherent quality answer. Being new to the platform could not be a pretext, for answering properly with a cited quote is a common protocol.
Now, how to handle such answers?
When the answer came at the First Answer review, then the feedback could have been shared:
As it’s currently written, your answer is unclear. Please edit to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers in the help center.
I assume the reviewer plausibly raised a flag against the post.
But the proper way would be to initially leave an explicit comment to bring up the issue in poster's attention.
Now that there is a legit comment that has already called on the poster to address the relevance of the quote in light of the original question, I would wait for some time in the hope that they might respond and edit their post.
If that doesn't happen, then I would recommend deletion with no comments needed for the existing reasons couldn't be resorted for the same: the link-only answer statement might resemble the tone, but it is not ultimately applicable, imo, here: the citation is there; the quote won't disappear (albeit with no context).
If you wish, you can leave a custom comment why you voted the way you did. But I feel the insouciance and subsequent absence of any reply to the comment raised speaks volume of the action that can be comprehended by other reviewers and the community at large about its inevitable fate.