I would say that using a website's own internal search is fair game, but good luck trying to find, for example, the link to a blog you forgot the name to. You can try Wikipedia, Youtube, StackOverflow, WaPo's article, but I doubt you'll ever make your way to that blog without the URL to it.
The funny thing is I never book mark. Most of the sites I visit I just remember the URL. On rare occasions when I can’t remember the URL, I’ll search for in on Google. Like most people, I use Google a lot when I’m looking for things I don’t already know, but not when going to my commonly used sites. In the early 2000s I developed a website for a local public radio station. One thing it thought me was the usefulness of “speakable URLs”. Since most pages I built would require someone on the air speaking the url, they had to be short and distinctive, easy to say, and easy to remember (since the listener wouldn’t be taking notes, they had to remember it long enough to get to a computer and type it in). That got me in the habit of just remembering the URL, which I still do to this day.