Isn't the primary (entire?) purpose of the embargo timeline to permit vendors time to develop, test, prepare, and rollout patches to prevent exploiting the vuln

Isn't the primary (entire?) purpose of the embargo timeline to permit vendors time to develop, test, prepare, and rollout patches to prevent exploiting the vulnerability and to do so before the public disclosure of it? I don't know if I'm missing some detail here (like perhaps there are two embargo timelines, one for code shortly before another for full release), but at a first read this seems like it's exactly what the Chromium developers should do.