I'm also planning to get a PhD in CS starting next year. But I think this question is irrelevant, in the sense that it is not the right one. Because of course t

I'm also planning to get a PhD in CS starting next year. But I think this question is irrelevant, in the sense that it is not the right one. Because of course the answer is formally "no", one can be a very good scientists without having a PhD. But do society needs people getting PhDs and people training them and the whole university system. Yes, definitely yes. And a PhD, even if not formally needed to be a good scientists, is an effective way to become a scientists since it's basically learning to be one with others who already are.