The need to jb has gone way down in the last decade, that is for sure.
I jailbroke my original iPhone in July, 2007, a couple weeks after the iPhone came out. That was an amazing time. Jailbreaking totally enhanced an already amazing device, and at the same time showed where things were going. At that time there was no App Store for the iPhone--there were no installable third party apps (at least not officially). But jb'ing allowed app installation and it was clear the OS, known as iPhone OS at that time, would eventually allow that. And it did with the App Store in 2008.
But there were still plenty of reasons to jb. BiteSMS was so far ahead of the text app there was no contest. MyWi was the only way to really tether. Plenty of other really good apps too. And loads of customization (granted I was never really into jb'ing for the visual customization aspect).
Over the subsequent years iOS gained more and more features, that beforehand needed jb. And Apple themselves hired jb devs to work on iOS. The guy behind Mobile Notifier, Peter HaJas, is one I remember. There were others.
By the time the iPhone 6 was released I figured jb'ing was about dead. I skipped the 6 for a Note 4 and embarrassingly predicted my Note 4 (AT&T) would be rooted (Android's version of jailbreak) well before the iPhone 6, if the 6 ever was. Boy was I wrong: The iPhone 6 was in fact jailbroken rather quickly. Meanwhile my AT&T Note 4 never had a real root (only one that lasted till the next restart).
A year later I did jb my iPhone 6S+ but by then I didn't see any real need and just did it because I could. I then started to run into apps that wouldn't even run if jailbroken and I said forget it (I am talking to you, Super Mario Run

). The end of jb'ing for me.
But thanks for the memories!
Mike