Have tweeted at you... I'm interested!

No.

I'm a photographer, and it makes my work a lot easier and faster. Since when do we "need" any technology. We don't, but it does make life better.

Create your own content. :)

Wrong. I'm running a Dell UP2414Q 24" 4K at 60 Hz off a 2014 rMBP. It's glorious.

I traded my 2011 27" in for a MacBook Pro with an external 24" 4K display... it's exactly the same as the change from non-retina to retina MBPs or phones. You can see the difference quite clearly.