Fixing mistakes without accepting blame or acknowledging the error always bothers me. Does it stem from the fear of a lawsuit-happy society, or embarrassment?
Having been on the other side a few times (the one who quietly fixed an error without acknowledgement), there are a number of other factors at work as well:
1. Sometimes, fixing the error is within my power but talking to the customer is not. For example, when I was at Google, I was an engineer - fixing a bug was something I could do merely with a code review, but talking to the outside world was forbidden by company policy, and I didn't even know who the people were that were authorized to speak to the outside world on company behalf.
2. Very often, the error is one of several dozen in a bug queue, and you just want to fix it and move on. Talking to someone - particularly a customer - is a big mental context switch; it means that 5 other people won't get their errors fixed at all.
3. Sometimes the error is a distraction from your normal job duties, you feel like you can do a good deed by taking 5 minutes of your day to tweak a config file, but you don't want it to blow up any larger than that, and usually once a user has your attention they feel free to ask you to fix all their other annoyances. This is a big problem with working on open-source software; I've never yet had a good deed take less than 5x the amount of time I budgeted for it, and usually involve a few people mad at me. (I often find out later that many other people are very appreciative, but the latter never seem to speak up).
I think the fundamental problem is a mismatch between our expectations as human beings, which are shaped by millenia of face-to-face interactions, and the reality of modern society, where we are just a ticket number to a faceless corporation. Internet companies like Google and Facebook have roughly a million users per engineer working on the product; Whatsapp has 50 million. Imagine the scale of insignificance of any one problem; by the numbers, a user of a consumer product is roughly as consequential as a hair on your head. That could be why we get such shitty service from basically every major consumer company out there.
"fixing the error is within my power but talking to the customer is not."
It may have also changed google's view on which people are searching for and visiting the site. Before, its search traffic was people searching for phone numbers, a random cross section of people who get spam phone calls. After, its a specific name brand being searched for by possibly well connected tech workers who are logged into google+.
In this particular case and specifically with respect to google (and their resources and profitability and for lack of a better way to put it "power") as well as how difficult it would be for those who are wronged to bring a lawsuit (and prove damages) I somehow strongly doubt that has anything to do with it.
The only thing that I think that google would fear is regulatory action (if even possible) or perhaps (once again if possible) a class action lawsuit.
For the most part, the people complaining about lawsuits have something to lose. I think there's a reason for that. Lawsuits are the first resort when the track record of the people with power is such that trying to convince them to act ethically does not seem plausible. If problems got resolved without having to go to the mat with powerful entities much, much bigger and with many more resources than you have, you really think this'd be a thing?