Re: Oh dear ...
My own experience is that there is too much emphasis on the dev of devops - what is being lost sometimes is the experience of Ops to keep the system stable is the most important thing (new features are great but unstable systems lose customers\business support). Ideally it's melding both sides. And that means making sure all the testing (including implementation dummy runs, reversion etc) is done before shit lands in prod. That dev's understand what works in prod and what doesn't because they need to support it with Ops and not just throw it over the wall.
As for the rose tinted past - most places don't do DevOps and IT is crap - heroic efforts to keep systems up, Change Boards where you can do any dangerous crap as long as you tick all the neccesary boxes, you can't make change x to the network in anything under 6 months, only god knows how the system was configured because we once wrote a manual but now it's out of date because we never had time to update it. Sure some won't have that experience but I'd guess it's a minority (at least at big IT places). If DevOps can be used to address some of those problems why wouldn't I use it?