If I was reading a book, and the author made an update, I wouldn't necessarily want the new update from the author. Notify me there's an update? Sure! Automatically replace the copy I'm reading with the update, simultaneously removing my ability to ever get back to the version I was reading? No thanks.
"What's there has blinded people to what is possible." As someone who has a good idea of what's possible, I tend to agree, and think of browser 'cookie' support as a good example. 'cookies' were lambasted as the embodiment of evil in the mid-late 90's. The hysteria around them was insane. Why? We had little control over the visibility of what a cookie was, what it said, and how to manage them. Even today, in 2012, cookies are little understood, and to 'manager' them requires multiple clicks in to layers of menus often marked 'advanced' or 'privacy' (both are silly labels for cookie data, imo). We could have given people easier access to view/manage/understand cookie data, and probably avoided national legislation like we see in some countries now, but that would have meant breaking the status quo. Far easier to focus on browser market share and "standards compliance" as the primary measurements of browser utility and acceptance.