Fixed bike vs. MTB chainring - who wins?

Both the ramped 9 speed mtb chainring I was running and the current 3/32 mtb chainring I have on my polo bike is running fine. I think your statement is pretty generalised and you only came in to problems because of the nature of the design of that particular chainring. One with a more uniform and symmetrical shape would probably have been fine.

I had posted the photo of my chainring, I understand some MTB chainrings might be ok. But in the future I will try to use components built for purpose.

I have to say it's pretty incredible that chainring collapsed after only 2 hours of light riding!