It's not obvious at all. It isn't even obvious if you spend 8 hours on research and are a techie.
What was the flagship before the Pixel? What was the flagship 2 years ago? The android market probably has a changing flagship every 6 months and even then it isn't obvious what it is.
Try typing "flagship android phone" into Google search. Pixel only comes up in 8-9 results out of 100.