Why do you believe Google is "really good at building useful products"? Would you buy any of them if they didn't have the Google brand (or pay for any of the free ones for that matter)?
10 years ago I certainly would have purchased Google Search, Google Maps, Chrome and Gmail. I currently pay for Android. Nowadays there are a lot more alternatives that have caught and surpassed some of these products. I have switched back to Firefox and am currently switching to ProtonMail but yes Google has made quite a few amazing products that for years had no competition.
I would absolutely pay $150 a year easily for access to all google products. Gmail, docs, chrome, search are the key apps for me.
I'm sure the Google brand has helped adoption, but I do actually pay for G Suite and it's pretty hard to beat if you're starting a business and want a pretty no-nonsense productivity suite everyone can work together on.