Not to be the 🤓 but technically that only applies to Euclidean spacetime. It is possible to have spaces in which loops occur without there being a localized curvature gradient. The manifold might loop but at a small enough scale all manifolds are locally Euclidean. There are also just weird things that happen in hyperbolic geometry where you can have infinite nested concentric circles that are all technically the same size and are centered at infinity (Horocycles).

Anyway, point is that we don’t necessarily know the topology of the space in which the loop resides, so we can’t make the assumption that the trolley would be destroyed.