If you’re a human being you are absolutely as capable of committing any evil as anyone else is, and people who do those evil things you haven’t are just as human as you are.
No one deserves forgiveness but God offers it to everyone.
The problem with dehumanizing people who do evil things or calling them monsters is that you think you could never be like that. The nazis were human. Pedophiles are human. Slavers are human. Everyone is capable of evil.
It also gives us the idea that some people are more or less deserving of forgiveness than others, or that we can justify our actions by saying they aren’t as bad as what someone else has done. The truth is we’ve all sinned against a holy, perfect God and none of us deserve to be forgiven. That’s why Jesus died in our place and that’s why it was the only way for us to be reconnected with God.
Nobody is “good enough” to get into heaven. No one has the right to see themselves as better than someone else. No one is good. Only God.