> It's a fairly straightforward conclusion that most visible stars are more massive than the Sun.

I can imagine that scientists have figured out accurate ways to measure the "actual" brightness of stars and including our sun, and maybe in retrospect using some simple insights and tricks, but it's not obviously straightforward at all.

Let's hypothesize that our sun is the most massive star in the galaxy, and what we look at in the sky are the rest of the stars in decreasing order of size, with the largest the most visible. How is it straightforward to conclude that that's not true? And are we declaring Newton's accomplishments straightforward?