It really goes back to the toxic incentives of ad sales. Google wants you to stay on Google.com so they get more chances to show ads. They only care about low quality results if it means you stop using them, which for years wasn’t a serious risk but can change relatively quickly if alternatives arise. They should know, given how rapidly they pulled users away from Alta Vista, Yahoo!, et al. 20 years ago.
So why do companies like Microsoft and Google push in this direction? Why are they making the results more and more opaque? You'd hope that they would care enough to be good stewards of the power granted to them through their information monopoly, but barring that, you'd hope that they'd recognize that people want results they can verify, not just random answers.
Or maybe they're hoping that people don't care about verifying results, hoping that people just want an answer that's not necessarily the right answer? It seems like a dangerous gamble.