They've tried experiments but it's not as easy as it might seem at first thought. Consider what happens with someone setting up a hostname like bankofamerica.secureuserportal.com or www.gmail.personaluserinbox.biz – a fair number of people will look at the left part rather than reading from the right so even displaying it separately won't help, especially if they don't have a huge window with tons of room and all they see is the first part of "www.bankofamerica.comsecurecardholderservices.ru".
Only displaying the domain name will help with that problem but it has usability issues for any company which handles user data under subdomains since it'd be harder to tell user1.example.com from user2.example.com if there's any possibility of spoofing.
In fact, if I was Google (and I was less scrupulous), that's the kind of behavior I would encourage: train users to type destinations into Google, serve up the results using AMP, obfuscate the whole thing by eliminating URLs, then users will just stay in Google's ecosystem and never leave.
And one of their incentives in doing so is that Google is an alternative to URLs. Already many users Google ‘facebook’ and click on the first link rather than just typing ‘facebook.com’ (or ‘face’ TAB ENTER).
Although I don’t believe I saw it in the article, it’s in Google’s interest to mediate all access to the Internet for consumers — this isn’t fundamentally different from Facebook’s VPN. It’s not in users’ interest, of course.
If they cared about security they could do something like display the domain & the path separately, maybe on different lines (with maybe colour used to distinguish HTTPs vice HTTP):