I’d kind of disagree, as noted above. Steve’s only code is “be the good you want to see in America and the world” and he will break any unjust law to follow it. He doesn’t uphold the Constitution or other laws in particular, he upholds the law when it helps and doesn’t when it doesn’t. Which isn’t to say that he doesn’t play by the rules even when it gets in the way, because he’s very aware that he’s a symbol of his country and his country can’t be seen to break international law, but that’s a matter of practicality.
Neutral good is basically “I’ll do the right thing even if there’s a law against it but I don’t break the law as a point of principle”, which is honestly most heroic characters in fiction.