The incentive system in academia is to produce people who cite their mentors in formal research. That's it. Because universities are non-profits, they go to the indirect incentives. This trumps any altruistic ideals. In their defense, most Phds in computer science are fully funded, so it's not transactional like an undergrad degree.
I've worked with several Phds with background in Stats and Computer Science. I found all to have "Good Background" - they knew a lot about their fields. Some were great at working with others, but some not so much. It wasn't a magical degree. Many regretted not getting the 5 years of work experience instead. Relative to the All But Dissertation crowd, they were a little better at Getting Things Done, versus just talking about things. (Very small sample size, so don't read too much into it)
I don't think your analysis of the incentives is accurate at all. If I were to oversimplify similarly, I'd say instead that modern incentives in CS academia, for non-tenured faculty at top research universities, heavily favor money, wherever it comes from (in large part because with budget cuts, professors have no choice). Grants are good, industrial partnerships are good, basically anything that brings in money is good. Citations are secondary, and used mainly as a stepping stone to bring in money. From that perspective, students going to a big company are good, especially a big company like Microsoft, IBM, or Intel that funds research. Students going into academia to write papers that cite the advisor are also good, but not as good as students who go somewhere that has money.
Academia has the same incentive system as other fields, i.e., a combination of money/fame/power and all three comes from doing great research. Great research will get you the citations regardless of the number of former students. Also number of citations is a necessary but not a sufficient indicator of great research.
I've worked with several Phds with background in Stats and Computer Science. I found all to have "Good Background" - they knew a lot about their fields. Some were great at working with others, but some not so much. It wasn't a magical degree. Many regretted not getting the 5 years of work experience instead. Relative to the All But Dissertation crowd, they were a little better at Getting Things Done, versus just talking about things. (Very small sample size, so don't read too much into it)