Why not just alert the user if the address bar contain something weird like this... And also, why not do something like this even. Let the browser save screen

Why not just alert the user if the address bar contain something weird like this... And also, why not do something like this even. Let the browser save screen shots of some user selected sites. Like mail login page, online banking login page etc etc and have them map to a trusted url. After loading a page, browser should screenshot the page and use some ML magic to compare it to the stored screenshots (I mean, there are things today that can call out the names of the things in an image and even what tell they are doing, right?). When one of them matches and If the url of the current page differs from the trusted url, the user should be alerted..Something like "Hey user, this page suspiciously looks like this page that we stored, but the url is completely different. Are you sure about this?"