That assumes that if a person is guilty it is possible to prove it, sometimes there isn’t proof.
As for the victim is not being crucified, this has been covered a lot, it is a zero sum situation, treating the accused as innocent until proven guilty means treating the victim as lying until proven truthful, and as often it is difficult to prove this is a big problem, as all the research and stats show how prevalent abuse is, how rare it is to get justice, and how rare false accusations are, balance of probabilities you are best to side with the victim. It’s also weird how generally when people say they are accused of a crime, I was robbed, I was punched, I was conned, the normal thing is to believe them, yet with abuse the response is so often ‘now then nothing has been proven’ it’s weird and only makes sense if people think false accusations are rife but all the stats and research shows that is not the case so it more likely just reflects people’s attidues and bias