1. ChatGPT first public release (I am not one who saw early GPT models) I think late 2023 iirc?
Why? Turing test bye bye.
2. Opus 4.6 w. Claude Code - not the model in partucular but happened to be when I started seriously trying to vibe code at home, as I saw all the hype on Linkedin. Yes linkedin sucks but it is somewhat a barometer. Around early this year.
Why? Knocking up decent enough web apps so quickly.