Hell is indeed full of people who rejected Jesus Christ and because every single person is born rejecting Christ, it is the greatest miracle this world has ever known that God would choose to save any by humbling Himself and coming into this world to be tempted in every way as we are yet without sin, who absolutely succeeded in His rescue mission to save those the Father had given Him by being killed by the will of God at the hands of evil men to pay the price they could never pay and satisfy that which an eternity in Hell could never do in His perfect, atoning, redeeming, substitutionary, propitiating sacrifice to secure for His people the forgiveness of sins and the guarantee of eternal life in imputing His perfect righteousness to them in His resurrection.
All who are humbled to not look to themselves but outside of themselves to their Creator and cry out to Him to grant to them by the power of the Holy Spirit, through the ministry of the true Gospel, a new heart to be able to obey His just command given to all to repent and believe on the Lord Jesus Christ will indeed be saved by grace alone, through faith alone in Christ Jesus alone, as revealed in the Word of God alone and to the glory of God alone!