As you can see in the screenshot, I am logged in https://stackexchange.com/ itself:
However, when clicking "Learn more" to reach the tour page, I am no longer logged in:
Clicking "log in" takes me through all the steps to create account on a new Stack Exchange site, eventually putting me back in the tour page, in the same state exactly.
The weird part is that the "Your Communities" list is OK and showing my own communities, so looks like it's a bug in the top bar somehow.