I'm Christian (Roman Catholic) - I don't necessarily disagree that we should aim to forgive, but before that can happen he needs to repent and take the consequences for his actions, which in this case means dropping out of public life for the remainder of his life. Christianity doesn't preach that there should be no consequences for our sins. He remains a wealthy, privileged man, with a happy family life. Not being a working royal isn't a harsh punishment, although the reputational damage must be hard to bear.
I think we ought to stop going on about it though, move on and allow him to move on - not by stepping back into the limelight of course, but by fading into obscurity.