> He capitalized on the turmoil to advance his own career. However, the department’s progress has ground to a halt and they haven’t had a good software release in years now. Doesn’t matter much for him, because he can now pivot to another company and show a track record of rapid advancement.

That's a genius move. He can also use his new position at the company to pivot their tech stack to mimic the one used at the place he'll be applying soon.