From my cubicle at work I can see four divorced monogamous women. Married young, didn't work out, their problems are out in the open for me to see. Do I think that all mono relationships are doomed because of those and other mono relationships that I know didn't work?
Nope. They just went in too fast and without the tools or the open eyes to either pick a good partner for them, or fix whatever was not working. Hopefully their next relationship of whatever kind works out better.
I like Ferret, though I can see that he isn't everyone's cup of tea and that's ok.