I made it clear that I feel it is different, on an emotional level. That's just how I feel, not a statement of fact or a claim that it is different.
And even leaving the ovaries intact, hysterectomy raises the risk of prolapse, premature menopause, and early dementia (off the top of my head). It is a major operation to go through, with more serious, long-lasting potential effects for the donor than a kidney transplant.
Plus, women are uniquely at risk of being trafficked, coerced, financially pressured, or even just socially pressured - 'you've finished your family, how can you withhold the joy of children from your sister??' - into undertaking this risky operation. Just look at surrogacy and egg donation, and how on a global scale it's resulted in many women being held prisoner, used like breeding animals.
The potential misuses are ethically concerning to me.