Yes, it's a no-brainer. Relaxing the incest laws would set back the protection of children and young people by centuries. As you say, we are only just beginning to talk about sexual abuse, and admit that it is endemic. But in a sense, nobody has a clue as to how to deal with it, and this would make it worse. The idea of investigating a father/daughter relationship to see if the daughter was consenting, is farcical - who on earth would this? Social services need this like a hole in the head.
Sexual abuse of all types is a nightmare from a legal viewpoint. The offence of taking someone's car without consenr, Twokking, is easy because you can see that unless there wasn't a previous relationship, you driving about on someone's car when they don't know you, is an open and shut case almost all of the time
However in the case of rape or abuse, people have sex with people they didn't know as a normal course of events. So trying to prove rape in that case such harder.
So take that into a family situation where twokking would actually be hard to prove, overlay that with statistics on sexual abuse within family and then work out quite how hard that would be to prove and then add in the taboo in even reporting this stuff that applies to victims.
Absolutely, wigginhall, this would be a nightmare for social services.