Vinyl windows from a house built in 1997.

I have the spring with compound pulley design on 5 windows. 9 of 10 pivot brackets were snapped off, as seen in the attachment. The design of this pivot seems extremely weak, especially given how much spring tension I have on the balancers. Is there a chance these balancers were installed with too much tension to begin with. These windows when they did work always seemed tight to me, but now that I've had them apart I think that it was the spring load I was overcoming all along.