Our view of sin and Satan affects how much glory we give to God for the salvation of a soul.
The common phrase "free will" implies that the will is free from something. Is the unsaved human will free from sin and Satan? If we accept what the Bible says, that sin and Satan are extremely powerful, then our estimation of the unregenerate person's freedom will change correspondingly, like two ends of a see-saw.
If we think lost people are only wounded, then our assessment of free-will goes up and the need for God's grace goes down. If people are wicked, then our opinion of free-will goes down, and our sense of how much we need God to intervene goes up. If we think Satan only tempts people (sometimes successful, sometimes not), our view of human power goes up. If we accept what the Bible says, that Satan invisibly rules the human race (1 John 5:19), our view of how much we need God to intervene goes up.
People have been blinded by sin and Satan, and only the power of the Holy Spirit can get through to them. But the Holy Spirit can get through to them! This is why all the credit for someone coming to Christ goes to God alone, because only the Lord Jesus Christ is more powerful than sin and Satan. There is hope for everyone!