Zuckerberg rejects coordinated slowdown and offers Meta's Muse delay as the alternative.

His argument is that every lab can pace itself without industry coordination, citing Meta's months-long delay of Muse from a planned April launch to September 8 for safety and security work, with the line that Meta "didn't call for everyone else to do this before we would." He endorsed independent evaluators and advisors as the industry best practice instead. Hold this against the Muse Spark open weights Meta promised August 10 and hasn't released.