Earlier quoted context omitted.
Nothing loaded from the web should be able to fiddle with any browser behavior, yet here we are.
The History API is pretty useful. It creates a lot of UX improvement opportunities when you're not polluting the stack with unnecessary state changes. It's also a great way to store state so that a user may bookmark or link something directly. It's straight up necessary for SPAs to behave how they should behave, where navigating back takes you back to the previous page. This feels like a reasonable counter-measure.
Can you unpack this please? AFAIK history stack is not preserved in the URL, therefore it cannot be preserved in a bookmark or a shared link.