I'm not sure I agree with the premise that gamification is bad. Many people need a push to do things that improve their lives.
The Fitbit example is one that jumps out in that it is there to motivate people into exercise. While I personally don't respond to comparisons to others, I do respond to data where I can compare my results and recognize that my watch telling me I did a good job feels good about the exercise I just did.
Kahn Academy is gamification of a form of education. Earning points for learning many subjects.
I think there is merit to the argument that Duolingo went a bit overboard with trying to guilt you into continuing, but I don't think it can reasonably be argued that trying to motivate people into language study is bad.
I think mentally, the author is probably just one of those like myself that doesn't respond well to gamification overall but the majority of people definitely do and it can help in self improvement.
That said, I totally agree about a gamified workplace. That strikes me as a slippery slope to an unhealthy relationship with work.