Not really. If I found a page that redirected me to a login, I would assume that that page is not intended to be publicly available, and that other content that I don't know about exists which is not intended to be publicly available.

I wouldn't infer that just because (as noted by the parent comment) https://twitter.com/ requires a login, I shouldn't look at https://twitter.com/twrbrdg_itself

Now, if all those pages I looked at before finding the login page had a banner saying "private, not for public consumption, don't share this with anyone who doesn't have an account", then I might think "hmm, perhaps I'm not supposed to be here".

That's not a fair analogy though. I agree that I wouldn't expect every page on twitter to be protected. But if you find a direct link to a random document indexed by Google, then check and the page that links to that document is protected, I personally anyway would assume the document itself was exposed accidentally. Obviously not everyone agrees though, which makes the reasonable person thing difficult to decide.

As for the lock on the door comment, I'd say it's more like if you noticed a store is left unlocked in the middle of the night, and therefore assume you're welcome to go in and walk around. In fact, they probably didn't leave it unlocked as an intentional invitation.

And how would a "reasonable person" decide that? That is kind of like say "if there is a lock on the door, you should know that it was meant to be locked. Yeah 7/11, open 24 hours, has a lock on the door.

We don't even have to make analogies; if it is protected information a "reasonable person" expects some kind of _obligatory_ login authentication, not an optional one.

Yes we have that, its name has changed recently because it was something like "good family father" (it came from greek democracy) and was deemed sexist.