When you say "cyberpunk" do you mean this game universe or the Cyberpunk genre?
While it's true most stories in the genre aren't all happy endings, it's usually about the lessons we learnt along the way. That said, this game is its own story so it can be whatever they want.
Not sure why ppl are so concerned with a happy ending, the most important thing is whether the story was good. A happy ending doesn't mean a good story and a good story doesn't demand a happy ending.