Should incest be legalized, like homosexuality was?

Originally this was brought on by me wondering why it was such a popular fetish, and why it was such a big deal to people that fictional characters were related and also in a relationship. The leap of logic in comparing it to yaoi fics or whatever came pretty naturally.

Culturally it's of course seen as immoral, but this kind of attitude shift has to start somewhere, and laws shape cultures pretty strongly. I'm not inclined towards it myself (not that anyone would dare say otherwise, but, y'know... trust me), yet tradition for the sake of tradition is dumb, and this seems like another case of "why does it matter to you who I fuck".

We also see awful things like parental abuse and sibling power games (oh how clinically worded), but these are separate things - abuse will still be abuse, legally.

As for the inbreeding issue, well, it's difficult to say whether the children of such couples would rather not have been born at all... and homosexual couples don't produce any children, so from a coldly clinical perspective they'd do more harm to the population long-term, since there's no possibility at all of a fully healthy child. Generally, I'd assume the theoretical couple here knows what they're doing.

Still, this popped into my mind just today, so I'm sure I've missed some things. Please do tell!