There's a lot in science that's mere observation.
The law of gravity is one example, since nobody knows where gravity actually comes from.
With gravity we see a principle which, when mathematically described in sufficient detail, is consistent throughout space and time. What we know of it, we know only due to the observations we can make locally and in our timeline thus far; however, even with such a limited view, we can already see that gravity very likely is as it has always been and is the same throughout the universe. This is certainly not true of neither Moore's law nor Eroom's law.
Please stop this. While I agree with your overall point, we know what causes gravity (the uneven curvature of space due to the distribution of mass). You can find this out by googling "what causes gravity". It's not a mystery anymore.
Moore's law does not pick up on any causal pattern that connects transistor size to time.
The universal law of gravitation does capture a causal pattern that connects masses to other masses.
Whether we "know" what causes gravity or otherwise is irrelevant.