Why Does Hell Exist?

In a basic model of atonement, human beings had generated a debt to God for offending Him with their sins. In response, God came down to Earth in the human form of Jesus Christ and endured the penalty for humans’ sins, saving them from Hell. If this is true, then why have we always been told that good people go to Heaven and bad people go to Hell? If Jesus truly endured enough punishment to pay the debt of billions of past and future sins, then why would Hell even need to exist at all?
I feel that if this model of atonement were to be true, there would be no religious boundaries keeping us from sinning. It would be easy to say “I can do that, Jesus has got me covered.” Obviously, modern law keeps us in line for the most part; however, we all do things on a daily basis that Jesus or the church would not necessarily agree with. We curse, we lie, we steal, we have sex before marriage, etc.
For the Christian way to have any plausibility, atonement would have to be much more complex. From a religious standpoint, perhaps Jesus’ death was to implore the human race to become a better group of people. Maybe the passion of Christ did not save us from Hell, but instead gave us all the chance to avoid going to Hell. Thinking of Jesus’s sacrifice, we have the opportunity to feel remorse for our sins, ask God for forgiveness and be forgiven.
From a historic standpoint, there are many religious instances in which stories were swayed to reflect the times. For example, during lent, Catholics cannot eat meat on Fridays. During the time that this rule was inducted into the Catholic faith, the world was experiencing a struggling fish market. Therefore, Catholics were told that it was sinful to eat meat on Fridays during lent in order to promote the purchasing of fish and improvement of the industry. Perhaps atonement is a similar situation and is not real at all. Maybe the writers of the bible used Jesus’ death to pass along his teachings to promote becoming better people. With atonement, Christ’s death was supposed to pay off our debt to God, when in reality, it only created a new debt, one to Jesus himself. Followers of Christ may now feel obligated to ensure he did not die in vain, making sure to ask God for forgiveness whenever they sin and strive to become the best person they can be. So, maybe atonement is just a way to instill guilt into human minds, making sure that those who followed Christ would do just as I mentioned above, the threat of a non-existent Hell hanging above their heads.
Therefore, in my opinion, there are three options when it comes to the existence of Hell. First, Hell existed at one point and was abolished after Christ’s death. Second, Hell still exists and Christ’s death has given us the opportunity to atone and avoid it. And last, Hell doesn’t exist, never did exist and atonement is merely a biblically manipulative tool to keep us humans from sinning.