Yeah they say "Adult Collectable", but they are supposedly tested for 4+....these may be considered collectables, but they are indeed toys, meant to be played with, and yet, they don't stand up to play, they loosen really fast, and some figures self destruct....
So I guess by your logic, Goddess and Snout are acceptable casualties of a modern mass produced line....yet the problems affected many of each figures run, that's not fragility, that's poor craftsmanship, poor materials, and just plain bad design choices, much like Stinkor's forearms & the black plastic issues.
Some people may have an unreasonable expectation for MOTUC, like every figure absolutely perfect....yes, there will be flaws, but for the price, and for the supposed "Adult" market....there are many figures that have too many issues, therein lies the expectations, getting what you pay for....and that is a reasonable expectation, no one wants to shell out $20+ for an action figure, that can't even stand, if that is the case, they might as well stay MOSC....and to say an unopened figure defeats the purpose, sorry, but that is in the eye of the beholder, and in the hands of each individual collector, toys can be appreciated and loved just as much in the package if said collector chooses....What defeats the purpose is saying someones collection habits are ridiculous if not met by anothers standards or how they think they should be collected, yet in the same breath saying it's OK collect as you like, I have no issues with that.....
My son has a He-Man, he's had it for about a year now, and it is still playable, and nothing broken, hence dies the fragility of the figures, but QC issues are far different from rather a figure is meant to sit on a shelf enjoying years of dust, or meant to be taken off and played with. Some figure break way too easily, and that is poor quality, not intended fragility due to a "collectable" status of the figures.