Hello!
The changelog in which we brought this feature explains the basic functionality:
This protection helps mitigate against a new form of WordPress query exploitation we discovered. This can be invoked either intentionally or accidentally, causing Google to crawl and index thousands of pages that shouldn’t exist.
The query-exploits we found won’t cause data-integrity issues, but it can cause some SEO issues, such as that your site keeps feeding Google freshly auto-generated pages that shouldn’t exist. With the option enabled, TSF recognizes these exploits and halts search engines crawling so that they won’t index bogus pages.
If you wish to learn how this works exactly, then here you can find the advanced documentation, PoCs, and code.