Both are important, but ultimately as you said, what the devs do trumps what they say.

As an example, that is why I refunded my Star Citizen pledge years ago: They made a lot of promises about what things would be like one day, but nothing they did ever seemed to align to those words. Lots of things like speaking out against pay to win and then being super reluctant to make content unlockable with anything other than actual cash....

What a developer does gives you a look at what they will most likely continue to do regardless of what they say.

So when Bluehole says "No microtransactions until release" and then puts microtransactions in before release? Expect more of it. Expect them to not go away, or to come back much sooner than expected. Expect cosmetics that are currently free to become paid.

The only thing I disagree with is that you seem to want to disregard everything the devs say and judge the game as if they said nothing at all. I personally believe both are important when judging the game. Who is making it? What have they promised? How does the game in its current state align to those promises? Is it even heading in the same direction?