I would find it difficult to understand how someone cannot want to know about their child and at least have some, nominal contact.
In years gone by, it wasn't an unusual situation; I can think of two people who had children and the father never met them (they may have in later life, I don't know), but in both cases the women didn't want 'dad' involved because he had let them down. Different times. The fathers did pay maintenance for their children.
Speaking as a mature adult, I would not get involved with man who chose to have nothing to do with his child; as a young, naive girl I might have done.
Timothy West has talked about being estranged from his daughter from his first marriage for many years and the circumstances. It wasn't his choice but he let it happen and will always feel guilty. Luckily he married Prue who got them back together and their two boys are extremely proud of their elder sister. You hear about one parent going to live abroad and taking the child, making contact extremely difficult; I think that isn't allowed now without the other parent's consent.
Each situation is different, I don't think we can judge unless we know both parties well and understand their thinking. I would be concerned about having a child with a man who already had one that he didn't see. Having said that, there are women and there are couples who abandon children but manage to rehabilitate themselves later.