I think collectors need to buy figures with the idea that they are figures and not action figures first. Yes you can place them in various poses but if you do it too much or put them in an overstretched position for too long they will definitely degrade and break down, no matter the material used.
Higher end figures also requires some knowledge to maintain them, just like you wouldn't place your sneakers with icy soles out in the sun (and allowing it to yellow or worse, drop off), buying a car and keeping the engines/tires tuned, you need to also understand that seamless bodies requires some small maintenace such as dusting it lightly with baby powder to keep it fresh, refrain from placing them under direct heat, etc.
If not, there are other alternative options like Play Arts Kai action figures that allows you to abuse the hell out of them with all sorts of posability you may think of, but they aren't that cheap either.