Years ago, if you wanted to know what someone was ... (
Two points to be made here:
First, while we all may assume that a search for "whatever" will yield the same results on Google or other search engines, the fact is that those results wil be listed with a priority based on your previous searches. So if you and I both Googled "black panther" you, because of your prior searches on large African mammals might see a bunch of results on page one relating to the big cat, whereas I might see the first page of results relating to the terrorist group in 1970's Chicago thanks to my previous searches. All of this is done in the name of "convenience", and if you don't think it through it sounds just dandy, right? (now it truth, my results will show the big cats as well, but on the 5th page or something, while you will get the terrorist group results way down on your results list, but who looks down that far?)
But contrast that to a paper encyclopaedia - where we all know that particular edition is the same - if you and I both look on page 48 (whatever) we will see the same thing. However, since we each assume everyone else sees the same thing we do online we end up being trapped in our little thought bubbles, unaware of other things out there. The same is true of social media (for those of you foolish enough to use it) - there too you are fed things they "know" will interest you (because all they care about is keeping you glued to the screen, not broadening your horizons) - contrast that to the old days of the newspaper, where we al knew a particular edition was identical, regardless of your, say, political persuasion. Again, this leads to isolating people through creating those "thought bubbles" or "echo chambers".
Second, and this is where things can get nefarious, is that those who control the media or search engine can thus essentially control your thoughts. To use an extreme or perhaps even ridiculous example, if the Alphabet company management decided that the Holocaust never happened (or at least that people ought not be aware of it) then it is not that big a technical problem to scrum all search results of anything "ugly". Over time, people would essentially forget that history - which some say is what certain political actors today are striving for - to forget history. Some here might remember a bit of (now forgotten) outrage over FaceBook having used 600K or so of its users as guinea pigs in an experiment, wherein they fed half of those users "happy" news on their walls and the other half "sad " news, all to see if that would effect those users' postings (which they did, duh). Furthermore, as relates to health issues, which is what Jerry first mentioned, how will you feel when the health insurance companies charge you differently due to your search histories, etc.?
And to he who said "well it's just capitalism" - wrong-o. This is technologically enabled control of the masses that simply did not exist 25 years ago, and we see that being abused by those in control. We now live in a time where a very tiny group of folks can control infinitely more than was ever possible previously, from your thoughts (see Facebook experiment mentioned above) to your behavior...the "social scorecard" being touted by some is one of the most horrible ideas ever thrust upon free society (the CCP loves it, though). Some will say "I don't care if they keep track of my every movement and purchase - I'm not doing anything wrong!" - but that belies a fundamental ignorance of the fact that it is those in power who decide "what is wrong". So while today few have issues with saying "well, buying porn is wrong" - how long before those at the helm can decide "buying ammo is wrong" or "buying large bottles of soda is wrong" or - well, hopefully you get the idea. And the CBDC (Central Bank Digital Currency) concept now starting to be bandied about ("hey! the Chinese have it and we are falling behind!!") that is even worse - in that it allows the government to surveil and control your every transaction (which is why tyrannical governments love the idea).
Before you get sucked into the "it's all just so miraculous and convenient" marketing hype, at least be aware of where it can lead. Just think of those 22,000 Denver power customers who discovered, when they had a heat wave the other week and the utility was concerned about power, that they could not lower their "smart" thermostats below 82 or something because the utility company overrode and took control of those same thermostats.