I don't think that it does.
I think that the (very small) influx of organs is not worth it due to the consequences of the actions. I think that pushing for education and a simpler organ donation registry is a far better answer than saying that someone can donate their organs for $x.
As far as kidneys specifically, there are some new innovations to help those in need and those willing to donate get matched up. If I have a sibling who needs a kidney and so do you, but you're not a match for your sibling and neither am I, there are now (a very small selective few) services that would work to put us in touch (in this hypothetical we would be matches for each other's siblings). The next step is making it so that if you're a match for my sibling, but I'm not a match for yours, that we could do a "chain" so that I could donate to a pool, you could donate to my sibling, and someone who is in need of my kidney could donate to the pool, and your sibling could receive that kidney (assuming the match).
Again, I see what you and Un are arguing for. It's not the product (organs, fetuses, etc) that is different to me, it's the process. You're incentivizing extremely dangerous behavior, and, as we have seen, this disproportionately benefits the wealthy and hurts the poor. When it comes to organs (because they save lives), I'd prefer if your socioeconomic status didn't determine the outcome.