“What about the millions who died before the Good News of the kingdom reached them? Is it fair to exclude them without them having a chance to be saved? How can heaven be a delight for anyone who knows that there are large numbers of people suffering in a hell that they had no possibility of avoiding? Why should they suffer for a failure to hear the gospel that was due not to their sins but to the sins of others? God wants his house to be filled (Lk 14:23); how can it be filled without them?
Elton Trueblood puts the same question to orthodoxy: ‘Such a scheme is neat and simple, but it is morally shocking and consequently not a live option of belief for truly thoughtful or sensitive persons of any faith. What kind of a God is it who consigns men and women and children to eternal torment, in spite of the fact that they have not had even a remote chance of knowing the saving truth? What sort of God would create men and women in love, only to irrationally punish the vast majority of them? A God who would play favorites with his children, condemning some to eternal separation from himself while admitting others, and distinguishing between them wholly or chiefly on the basis of the accidents of history or geography, over which they had no control, would be more devil than God. In any case he would not even resemble Jesus Christ, and thus is a contradiction at the heart of the system. The effort to glorify Christ as the only true revelation of God presents a conception of the divine that is incompatible with the picture which Christ himself gives.”
(Clark H. Pinnock, A Wideness in God’s Mercy, pp. 149-150)
I think there‘s a good answer to the difficult question, and that it isn’t universalism.