How should we digitize tracking employee engagement to reduce the management burden?

I was just asked "How should we digitize tracking employee engagement to reduce the management burden?"

There is a dangerously flawed assumption in this question that engagement can be digitized.

Measuring employee engagement cannot be boiled down to a simple equation based engagement metric. Employees must be actively engaged by their managers in order to assess engagement because people are enormously complicated. Reducing engagement to a numerical metric is overly simplistic like reducing friendships to a 1-10 score. It is impersonal and unfriendly. Each employee must be uniquely addressed and managed.

Quality management is not scalable through technology but only through a managerial cascade down the ranks with demonstrated proper listening, learning, and leadership, reaching every rung on the corporate ladder. 

Consistent 90-day reviews where employees are encouraged to voice their concerns and frustrations, which are heard and consequently acted on or more properly informed, will lead to an 'engaged' workforce who exerts their intellectual willpower to the company's problems.

In short, when standards of quality management are baked into the company culture, the engagement problem will solve itself.