I overall like how WotR handles alignment, but I will agree that when it comes to lawful in particular, it doesn't do very well. It's better than their first game, but still stumbles. There's a point where the lawful option is actually telling a cleric to betray their order's teachings, which is insane to me. A lot of the lawful choices in the game do feel a lot more lawful evil. I will say though that your vision of lawful good doesn't map perfectly to what the setting's idea of lawful good in general is. Since there are a lot of gods, and several of them are explicitly neutral, chaotic or even evil, so obeying them wouldn't be the lawful good action. Being lawful tends to be (or at least, should be) more about maintaining order in general, standing by tradition and discipline, obeying laws, etc. But really, other than the part about specifically obeying God, your idea of lawful goodis pretty much what lawful good SHOULD be in the setting. At one point you meet someone who expresses more or less that viewpoint. His specific phrasing was "good is the greatest order and order is the greatest good."
Onto alignment in BG3 though, I don't want Larian to introduce alignment because I don't really have faith that they'd be able to tackle it with the proper thoughtfullness and nuance such a thing needs in order to not just feel frustrating.