I think of it as a death cult. Thinking we know all that there is to know about the universe to the point where we can declare with 100% certainty that any particular thing will happen is not scientific.
Really? We are far from really understanding gravity, but I can very confidently tell you that if I kick a ball its trajectory will be a parabola (roughly, as a first order approximation and ignoring things like friction, which we can also calculate to a decent approximation). We can say where it will fall and give some confidence interval depending on the conditions and such. There is nothing unscientific about it.
Thermodynamics is not magic. In the same way that we can predict the evolution of climate without knowing where every single cloud will be, we can make statements about the evolution of large systems even though our knowledge of their state is imperfect. Again, nothing unscientific about it.
You can say what you like. Science is not about certainties. You can only control experiments to a particular degree and have no control of confounding factors which might interfere with your experiments. Do you really want to compare the totality of all universal processes to such trivial examples? I find it absurd.
You did not qualify the complexity below which it is acceptable to be certain of something so this is unlikely to be productive. You said that certainty was impossible and I gave you examples of certain things. Besides, both a ball and a glass of water are insanely complex systems. I am not sure we have the same definition of science, to be honest.
Thermodynamics is not magic. In the same way that we can predict the evolution of climate without knowing where every single cloud will be, we can make statements about the evolution of large systems even though our knowledge of their state is imperfect. Again, nothing unscientific about it.