The development in camera technology and the boom in social media go hand in hand.
Previously, before social media took off, cameras in smartphones were not so important.
Now, with the social media boom, you can take a great image and upload straight to social media to share with family and friends instantly, whenever and wherever you are. You cant do that with a traditional camera.
So yes, its a convenience thing - what's convenient for one person may be an inconvenience to you. Its all about catering for the masses, and the mass market love their photos and love their social media. As a company looking to make profit, Apple have simply catered for their largest market.