The CEO and upper management might simply not care about the long-term viability of the company. Cashing out in the short-term sounds more like what these executives generally do.
It only sounds like what they do because you only ever read stuff written by people who believe that without any evidence.
Sundar Pichai has been with Google since 2004.
But speaking in general, there is limited correlation between executive compensation and company performance. You can DuckDuckGo it if you want to find the evidence for this statement.
Having everyone you've worked with love you and find you brilliant is not at all the same thing as being brilliant.