If you have certain pages which have been indexed, and subsequently you decide to block those pages via robots.txt, will search engines eventually drop those pages from the index? (Specifically Google)
I know I can manually remove URLs with the Google URL removal tool as long as they are blocked by robots.txt or return a 404. It's stated that the pages returning 404 will be dropped eventually anyway. But I couldn't see what happens over time with pages which are just blocked in robots.txt if you do not manually remove the URLs.