China's population is dropping, so to the extent they had housing for their peak population, they will have increasing capacity to accept migrants. Their fertility rate has dropped to 1, one of the lowest in the world, despite having now lifted all restrictions on number of children and actively encouraging larger families, so it will become a precarious problem for them soon.

China's migration policies have been extremely strict, so to what extent they will be able to loosen that up without political upheaval is still an open question. So far they've only loosened up the restrictions on internal migration.