I assumed there would be plenty of land in China, is just completely remote or do I just have a completely incorrect perspective on China (generally speaking I’m sure I do, I’ve live my life on the other side of the planet)

There's plenty of land in China. There aren't plenty of empty plots that would be attractive for people to farm. I'm not so sure that has much relevance to modern immigration, though.

There is .. with the last of the subsistence farmers already living on it. There is basically no good unoccupied agricultural land in the world. The American settlers never appreciated how much work disease did in creating a seemingly empty space for them.