Their business model was give away and capture. Give away much of the possible revenue stream in order to lock in students, learning centers, governments, offices, and hobbyists.
That method of success has been well documented and replicated world wide.
The above method is how Google’s horrible products are currently winning.
Google is a serial murderer of its own products and services yet governments, schools, and companies fall over themselves to use Google products.
Capture is a valid, and proven, revenue strategy.
I doubt Gmail is going anywhere anytime soon, even more so on the workspace plans and for our company anyway that's the biggest Google product we bought into, ignoring Adsense, which is also going nowhere anytime soon.
Google drive also seems like one of those long support products but regardless for enterprise trusting a single cloud provider to host all your data is a disaster waiting to happen and most have on prem plus two clouds