That's a very general and simplistic view of things, and we both know it's not true. While URL's were designed originally to only provide an address for a specific resource we all know they are also used for storage, user state management and many other things, again not ideal but in some cases unavoidable.
Not to mention that URL's are not implicitly intended to be shared outside of the scope of your application you wouldn't link the 3 mile long URL that you get every time you login into your bank account would you?
> That's what the History API is for. When you add an anchor-tag query, store the original state in the tab's history.
Technically (best kind of not true) not true for the Google History API and even if it would be applicable for this it doesn't work in cases where you for example weren't signed in or explicitly blocking google tracking API's and services.
Not to mention that making a API call every time you need to do something as basic as backtracking on your search is just pure insanity when it comes to resourcing.
And if you are talking about the Chrome Page History API then why in god's name would i want a site to access it, not to mention it's not applicable in this case either.
> Infoleaks are BAD. The least Google could do is use their URL rewriting powers to remove the original query when they add a query stored in the anchor-tag. Life is bad, if this was in a link which was automatically shared (although all those pin URL generators link 10 fold more data than Google) I would agree with you, otherwise not really this isn't a use case for the application.