Ever since Sundar, a McKinsey guy, took over, the writing was on the wall for all of the bets that Sergey and Larry engaged in. He just cares about the bottom line (as some would argue he should), and doesn't have a "passion" per se. He's more than happy to just keep the train rolling, and keep the perception of growth up by showing more ads and using dark patterns[1] to make users click on what they think are web links but are actually ads. Eventually the train will run out of steam, and then its on to the next gig.
[1] https://news.ycombinator.com/item?id=22107823