 Why did Facebook buy WhatsApp?

Obviously with the single intention of killing a competitor.

It is impossible to make money off WhatsApp as it is because of end-to-end encryption.

Facebook just clearly bought it to prevent it from actually growing further and killing facebook.

It is mindblowing that the sale wasn't cancelled due to anti trust.

The outcome of this is that WhatApp will remain with the same feature set forever, while other competitors have been growing, notably Discord and Slack.

It seems that there is a case looming 10 years after the fact: www.cityam.com/facebook-fails-to-block-antitrust-lawsuit-over-whatsapp-and-instagram-ownership/ Wake up???