From my experience, the "PhD or not" depends entirely on the field being studied. In chemistry, the PhD is the union card that allows you to enter industry at a higher level and allows advancement if one's lucky/good to quite high levels. The BS/MS folks enters with lower ranks and face a ceiling about the point where PhD's enter. Similarly, the MD has all sorts of advantages to those who have studied medical-type fields at lower levels.

Conversely, nobody hired CS PhD's outside of think tanks or academia as far as I can tell. Similarly, engineering PhD's seem tracked to academia.