The assumption that you and I and most people who use the internet make is that what we're typing into the white box at google.com is a web search query, the kind that we made in the 1990s.

Google has never assumed that is what the box means, and they have the hard data in practice to know how many users treat it that way vs. how many users treat it like Scotty picking up the mouse and speaking into it in Star Trek IV... And they try to match the system behavior to whichever model best fits the average user.

(Back in the day when I was a Googler, a chronic complaint was Chrome conflating the nav bar and search results, and one of the reasons Google did that is they had the hard data on how many people went to Facebook every day by opening the Google homepage, typing "facebook.com" into the search box, and clicking the first link).