In a nutshell, yes, it kinda is a sort of butterfly effect. But look, you go to school and they drill into you until the cows come home that quantum mechanics

In a nutshell, yes, it kinda is a sort of butterfly effect. But look, you go to school and they drill into you until the cows come home that quantum mechanics is time-reversible, and gravity is time-reversible, and you just assume this is always true. But turns out, all that's needed is a bit of small-scale fuzziness due to QM effects, and then particle ensembles of 3 or more are suddenly not time-reversible anymore, though each of the basic laws still are. For someone like me this was a small shock.