I attribute the curriculum shift to something slightly different, which is the changing perception of CS as a career.
When I was in college in the late 1980s, CS was not perceived as the moneymaking career it is today. Accordingly the kids who went into CS were typically the nerds and hackers who truly loved the field.
Many kids now perceive CS as a safe, lucrative career option akin to becoming a doctor or lawyer. It attracts many students who are smart but perhaps not as intrinsically excited about the field. The universities adjusted their curricula to what these students care about: Less beautiful theory, and more practical training.
A similar thing happened in statistics. At one time it was hardcore stats nerds. Now "data science" has brought a ton more people into the field and the teaching methods have changed dramatically.