Something like this is 3+ years in the making. I found an article from Jan 2020 showing trigger was on board before the game even launched. Before they can announce partnerships like this things have to be approved in the pipeline for a while or you risk bad press if it falls through.

https://www.theverge.com/2020/6/25/21303233/cyberpunk-2077-anime-edgerunners-netflix-studio-trigger-2022-release-date

Edit: Heck even Arcane was pitched between 2014-2015. It took 8 years to come out, but it wasn't from an already existing anime studio so developing strategies for how to make it probably took some major logistics to do in house.