Screenshots disabled on posts

Grapevine 🍇 Not sure if it's a bug. If it's implemented as a feature I'm curious to know if the engagement has increased by implementing this. I was trying to send a screenshot of a hiring post to my friend and all I can see is black screen. I personally came to know of this app by encountering GVs screenshots posted online. I know it's forcing someone to use the share button and thereby use the link to download the app. Forced download of an app would help someone? Not sure if someone would download a app just to look at one post.