I would say they are more like a funnel. And they are trying to make their funnel even bigger. They make their money by sending you to other websites and services, which is why most people don't consider them a walled garden.
Their mail and calendaring apps sure don't, for example.
At this point Google is big enough that generalizing about how they make money is a bit pointless, because they have a bunch of different revenue streams. The only commonality is advertising.
Sure. They're way better than many about vendor lock-in, because they do realize that it's somewhat evil. Not to mention often counterproductive.
But that's not stopping them from signing deals to get Chrome drive-by installed on users' computers, say. Again, it's a big place. Some of it is still all about "do no evil", while other parts seem to be run by scumbags. Pretty good for a large corporation, all things considered, but not exactly all wonderful.
