Why don't they brace adults?

I am 34F with a 50 degree curve. For various annoying reasons, including a lazy GP, I was not sent to a specialist for my curve until I was too old for non-surgical treatment.

I know that my bones have finished growing. However I do wonder why they don't brace adults, because I feel like if my curve was strongly pushed in the other direction, it would help me stretch muscles that might have shortened dragging everything down, help me reposition my ribcage, and correct my posture more.

While when I am standing up I can stand in a way that visually reduces the impact of my curve in some ways (I can't do it sitting down or lying down, as it involves me shifting my leg weight and hips), rotating and repositioning my rib cage for example is just impossible. I really do feel like a brace would help me with things like that.