With high quality User Involvement, people are using your product when their lives call for it and in a way that allows the product to fulfill its promise to the user. This is distinct from how high user engagement is generally conceptualized in product world, which is when people use your service as much as possible.
Designing for engagement is unsustainable. It’s an outcome that is often at odds with what the user actually wants from the app, as is the case with much of social media. People are irrational, but they’re not stupid. They’ll resent the app, and eventually stop using it.
On top of that, engagement is an outcome! If I were to try to just design for engagement, it would be very challenging because the inputs are unclear. User involvement is defined by what the user is doing, which ultimately determines the user and company outcomes. Ask yourself - what outcomes are actually desirable for the user and the company, and what involvement is required from both the user and the company to make those outcomes happen? This is what it means to Satisfy the social contract between the user and the app.
I don’t particularly care about how many daily active users we have if the product doesn’t need to be used daily to accomplish User Goals. I’m not trying to violate the contract.