It's not love to let them die in sin. It IS love to warn them.
People misunderstand the nature of God. Yes, He is love and sent His Son to die fore our sins, so that we don’t have to. He’s also a God of wrath and slow to anger. The idea that God is turning a blind eye to sin and anything goes is erroneous. Jesus taught more about hell than he did heaven. The ignorance of the Bible is truly astounding!