Re: Precedent has been set...
"One does not HAVE to type http://google.com into the address bar and press return. With MS, there was no alternative installed."
Key word - "installed". Back in the browser wars era, even with IE bundled, I could have searched for and installed Firefox or Opera.
Similarly, if I were to install Chrome right now, I could type "http://www.duckduckgo.com" into the address bar and search from there. However, if I enter something that isn't a web address, it goes through Google's search.
There were browser choices then, and there are search engine choices now. What there is very little choice in, however, is what happens when you are on the web - and this is the crux of the problem. Regardless of what search engine you use to get there, the chances are that the site you're visiting will have Google analytics and tracking. So regardless of what search engine I've chosen to use, the chances are that Google have data about me.
Hell, the entire SEO industry is founded on the principle of trying to second-guess how Google wants your web page to behave and jumping when they tell you to. I don't hear any talk of Duck Duck Go analytics or rankings...
So - coming back to the idea of choice: there were other browsers available, but because Microsoft had bundled IE with Windows, and so the average Joe didn't bother looking any further. In other words, the reason the issue came about was awareness. Now consider searching the internet for something... except we don't search for it any more, do we? We Google it. Yes, just like "Hoover" for example, "Google" is now part of common parlance as an adjective. So people don't learn about choice, they learn about Google, just like when Windows told them to use Internet Explorer (conveniently bundled) whenever they wanted to get online back in the day.
And so we reach the present: Google has managed to get such a stranglehold on the web that major players are forced to bow to their will, or suffer loss of ranking. Other search engine choices get little publicity (or are tainted by their parent company's past), and even if we do use another search engine, unless we go out of our way to avoid it, our data is Google's property if we want to do anything on the web.