What is the use and benefit of static content signing in Magento 2 ? Is it recommended to disable it from backend ?
It's best to keep Static Content Signing Enabled due to it's performance benefits.
You can read more about it on the Magento 2 DevDocs - http://devdocs.magento.com/guides/v2.2/config-guide/cache/static-content-signing.html
Static content signing is one of those Magento feature which solve the problem of browser cache on client side, for example if you have changed the css/image on a web page with same url, normally browser will cache it and in order for user to have the updated css/image, they need to clear their browser cache untill it expires. Magento solve this problem by invalidating the browser cache for static resources by adding a deployment version to the URL of static files.
So now each time if something is changed in the static files, Magento will change the url which will force browser to reload the updated css/image.