That's because due to modern PWAs (and less modern POST requests and cookies) you can bookmark a URL and it still won't actually work when you try to recall it. It's become a feature for power users.

For example, a naive user will think they can bookmark their shopping cart page and that'll snapshot the exact items in the cart.

I've noticed people tend to use their website's native bookmark feature, like insta saved posts, or they share pages with the google app to save them to a list. If a site has a Share button then you at least know it'll work.