Possibility to activate default expiration date for shared links.

I would like to have the option to set a default expiry date for links to shared files. Intention is to increase the security of my files. I sent email with Dropbox link to the file, but by default, the shared link is valid indefinitely. It would be better to set (i.e. 'Settings > Shared' section) ON/OFF 'set default expiration period for shared links'. I could choose from a dropdown 1-30 days for instance. It would be great to automate all sharing and increase security.

I don't want my link to be active in someone's inbox(email) forever. And deactivation (unsharing) previously shared old links manually is a waste of time.