They wouldn't have combined the products and created a platform if they didn't plan to expand it. I thought about how significant it'd be if Google included some sort of website builder along with the Google My Business platform. They organically have more reach with SMBs than any competitor can afford to buy. That combined with the high switching costs of websites and they have a massive opportunity as long as they don't misunderstand their target market.
Now they're offering domains and teaming up with some of the biggest website builders out there. I'd wager that 1) it's only a matter of time until their domain service is offered as part of Google My Business and 2) they offer their own website builder/CMS.
The website builder industry is competitive and noncompetitive at the same time. The companies that spend the most on marketing have the shittiest products and the companies with the most product potential 1) don't advertise or 2) don't cater to small businesses as much as they should. They're all asleep at the wheel in one way or another.