I'll respond to this on the off chance it is aimed at me. I mentioned those specific game theorists because I felt others in this forum might like to look into them. Aarseth, for instance, defined games as falling into a super-category he called ergodic literature: it just means that work must be done to traverse the text. My view is that games are simply the tools for doing that work, and I specifically think that the sort of tool game rules are involves enabling, shaping, defining or limiting acts of leverage over (in order to produce) constructed narratives. We accept them only because of the ability they afford us to construct the narrative we are interested in, in a way that is interesting.
Reiland is significant because he digs into what it might mean for games to be constituted by rules. To say X is constituted by Y is just like saying bricks constitute a wall. There is no deeper mystery to the "jargon" than that. Reiland develops a theme that runs through game studies that I think is first expressly stated by Suits, when he talks about playing games as accepting inefficient means to achieving a goal just so that one can enjoy that experience. What he calls the lusory attitude. It is worth reading Bernard Suits.
If some philosopher in your experience has denigrated science and scientists, and made you feel they think of them as lesser, then in my opinion that philosopher was foolish. The philosophers I know are very conscious of the limits of what can be done and known without the methods of science. They likely think more of philosophy as tackling questions that - at least where we are today - are not approachable by science (questions of culture and language often fall into this category), and understanding how to frame questions that are worth answering (including metaphysical questions, many of which in the past have turned out to be fruitful once they were able to be investigated scientifically), and ensuring rigorous thought generally. What counts as reasonable? Justified? Free from self-contradiction and so on. Philosophy of science is an important area in itself, and can guide scientists to doing science better. It also provides tools for resisting current strains of anti-science.
So far as I know today there is no science that gets at the meaning of game rules. How we know what they are? Why we should accept them? I think in time - with the evolution of AI - that will change. A saying I like is that "a cat can look at a king" - for now, game theory or ludology offers a way of studying and coming to some reasonable and consistent explanations. We can look at something, and think fruitfully about it, even knowing that we can't see - or test - all of it as adequately as we might desire.