Ultimately, there is some value in each position, and in a corresponding set of positions on the left. Unlike many issues in US politics, in the long run this one is not well left-right aligned, and there is no single correct number for how much immigration is best. It's a bunch of trade-offs, which should be made democratically and end up somewhere around the number that the median person wants, such that roughly half of us are unhappy because too many immigrants come in and roughly half unhappy because too few. Arriving at that number and changing it slowly would be far better than wild swings.