Cyberpunk 2077 was announced a long time ago- back in 2012, before even The Witcher 3 was announced (and we are almost four years removed from the release of The Witcher 3 at this point). So why has it taken so long to come out?
As it turns out, CD Projekt RED was busy working on The Witcher 3 itself for a large period of that time. And then, even when the game did come out, the studio was busy working on its excellent expansions Hearts of Stone and Blood and Wine. And development on Cyberpunk 2077 didn’t properly begin until Blood and Wine was out in 2016, according to what French outlet Jeuxactu was told by Cyberpunk 2077’s lead cinematic animator Maciej Pietras.
To be fair, it seems like Pietras does get some of his dates wrong (he references a Fall 2015 release date for Blood and Wine, whereas Blood and Wine was a 2016 release—so either he means Hearts of Stone, and just misnamed the expansion, or he misspoke the date). Regardless of the confusion, however, I think we can safely conclude at this point that full fledged development on Cyberpunk has been underway for at least three years (I guess making a fully handcrafted world adds to that development time). Now whether or not that is enough to get the game out this year remains to be seen- recent speculation has suggested that that might end up happening.