This is a great answer - and this doesn't just affect products with hundreds of millions of users. It's a classic case of Innovators Dilemma (https://en.wikipedia.org/wiki/The_Innovator%27s_Dilemma).
This is a case of Google not seeing the cost/benefit equation being positive between changing the UX from it's current UXs to some other ones (within the same technological paradigm).
Sure, it might be a case of resource dependence and a lack of will to "start over". But that doesn't imply disruption as described by CC (at least not originally)