This is such bullshit. There is a big difference between googling and searching your own files, while the anecdote you give probably accounts for only 1% of that computer's usage or even less. Reading this opinion I even pictured a stock-photo with family members gathered around a laptop, stupidly laughing at a photo of "bread pudding".
Your sister could be searching within her own files for strings like "last year debt", "ass ventura crack detective", "bondage", "dvdrip" and "office keygen".
I'm sure your sister doesn't do that, but other people do. And searches can express and hint to your deepest desires/taboos and things that might lead one to think of illegal activities.
My non-technical wife asked me one day, during a funny conversation about sex gadgets, if people at Google can see what she's typing and I taught her how to use incognito mode. At some point I also made her aware that Facebook sends and publishes her lat/lon coordinates when typing a message from her phone. She understood the dangers of online activity and took steps to protect herself, without me even trying too hard to explain, but this required some amount of education which is out of reach for most normal people who either don't have a technical friend that understands such issues, or that technical friend thinks it isn't a problem, such as yourself.
Your sister could be searching within her own files for strings like "last year debt", "ass ventura crack detective", "bondage", "dvdrip" and "office keygen".
I'm sure your sister doesn't do that, but other people do. And searches can express and hint to your deepest desires/taboos and things that might lead one to think of illegal activities.
My non-technical wife asked me one day, during a funny conversation about sex gadgets, if people at Google can see what she's typing and I taught her how to use incognito mode. At some point I also made her aware that Facebook sends and publishes her lat/lon coordinates when typing a message from her phone. She understood the dangers of online activity and took steps to protect herself, without me even trying too hard to explain, but this required some amount of education which is out of reach for most normal people who either don't have a technical friend that understands such issues, or that technical friend thinks it isn't a problem, such as yourself.