>>510065856 (OP)One potential way out of this could be for them to utilize a stringently enforced temporary visa similar to the UAE / Qatar's programs for S and SE Asian laborers that primarily involves manual labor, and strongly limits the potential for diffusion / replacement, yet remains attractive for people in the source countries, as their living conditions are so poor, cleaning / building stuff in the heat of summer for minimal pay with subsidized housing would literally be an improvement for many of them.
It's something I could totally imagine China doing, and would be quite in character for them. Right now, iirc, they already run similar arrangements for several SE Asian countries like the Philippines, like with Filipinas becoming maids / cleaners in Chinese households, who habitually visit the Philippines on holidays, etc.