2021 January - Birdwatch launched with first 1000 users
2022 October - Elon acquires Twitter
2022 November - Birdwatch renamed to Community Notes
2022 December - Community Notes feature made available to tweets around the world
Maybe Elon pushed the release schedule timeline up, but it would not be correct to state that pre-Elon Twitter didn't develop and launch the feature. It had been live for almost 2 years by the time Musk showed up.
2022 October - Elon acquires Twitter
2022 November - Birdwatch renamed to Community Notes
2022 December - Community Notes feature made available to tweets around the world
Maybe Elon pushed the release schedule timeline up, but it would not be correct to state that pre-Elon Twitter didn't develop and launch the feature. It had been live for almost 2 years by the time Musk showed up.