This is an extremely valuable feature for those who have to add\modify some text on a web page. Just like for example in this very web form where I am writing the message right now. Imagine, you are switching temporarily to another tab to check something or get some expiration. Then you want to go back to the previous page and misclick the close button. Bahm, all of your progress is lost. Yes, you can refer to all kinds of workarounds and “wise” thoughts about proper tools for such tasks but on the other hand, simply removing one little button would solve this problem. At least an option for power users, let it be hidden but give the users a right to choose on their own.
I’ll propose this to the team though – maybe there’s a particular reason it’s not done.
Knowing the roots of such a decision would have been nice.
By the way, FF also removed this feature, though it is still available through modifying userChrome.css
This issue probably roots in the chromium itself.
P.S. I use ctrl+shift+t a lot