AMR considers that only people who believe in the historic confessions are Reformed. However many (possibly a majority) of the Reformed community believe that Reformed views can develop and have developed beyond the 16th Cent confessions. Of those people, many do not believe that God predestines anyone for damnation.
What do we see as an alternative? I think it's mostly an issue of how we conceive of God. As long as God can see the future in detail, and is omnipotent, I don't see how to avoid the conclusion that he's responsible in some sense for history. I think what people object to is the idea that God intends to damn specific people. That he adopted an approach that includes that is hard to avoid. But I doubt that he set out to damn anyone.
I don't know his thinking, and I don't know what options were available to him. But I think it likely that he couldn't achieve the goals he wanted without real alternatives, and that this resulted in some people being damned. No doubt he chose the best outcome, and that when we see him face to face we will realize that his choices were both just and loving. But there are enough statements in the Bible about him caring about the whole world that I think we should avoid statements that imply that he wants anyone to be lost.
Here's a statement that was added to the Westminster Confession by the Presbyterian Church in 1903. This is prior to the split-off of most of today's conservative Presbyterian churches.
"First, with reference to Chapter III of the Confession of Faith: that concerning those who are saved in Christ, the doctrine of Gods eternal decree is held in harmony with the doctrine of his love to all mankind, his gift of his Son to be the propitiation for the sins of the whole world, and his readiness to bestow his saving grace on all who seek it; that concerning those who perish, the doctrine of Gods eternal decree is held in harmony with the doctrine that God desires not the death of any sinner, but has provided in Christ a salvation sufficient for all, adapted to all, and freely offered in the gospel to all; that men are fully responsible for their treatment of Gods gracious offer; that his decree hinders no man from accepting that offer; and that no man is condemned except on the ground of his sin."
I'm not sure this even contradicts classical statements of predestination. Many conclusions that people draw from this doctrine are wrong. But I think mainline Reformed Christians are a bit more concerned about avoiding language that might imply that God has ill will towards anyone.