I have dealt with more of those latches than I would have liked. It is easy to critisize the metal use, but what would be a better choice? Steel will rust, brass is no stronger, and whatever you use, it must not promote electrolysis in the aluminum frame.
Also, the charge that "cost saving is paramount" is scarcely justified given the high cost to produce a part that has such a simple function. No, I can't help but think the promblem here is an engineering one: given the challange of keeping a window shut, someone got too clever by half.
But we have what we have. To make the most of it, it seems important to me to adjust the latches properly. Get them too tight on a bright summer afternoon, and something is going to break some cold winter night. I adjust mine so the will just, and I mean JUST, latch snugly.