The technology for it that currently does not scale to higher egg consumption rather well among other potential problems
They have not yet tried to sell the technology to the US egg industry but, even if they did, the volume it can handle is currently too low for this technology to be used to get rid of chick culling across the board.
[…]
One issue that complicates these efforts is the difficult-to-answer question of when an embryo becomes a chick. Some researchers say day seven is when chick embryos can begin to experience pain. If that’s right, sexing the eggs eight to 10 days after incubation as Respeggt does, and 14 days as Agri-AT does, may still end up inflicting pain on the embryo, which could be trading one animal welfare problem — culling — for another