I performed MD simulations all throughout my PhD, on three different supercomputers as well as on a virtual cluster I set up on Azure. I didn’t say latency wasn’t a bottleneck; but the parent poster asked why additional bandwidth would be needed. It’s definitely necessary, but not sufficient.

I would argue though that for simulations with very long-range force fields or ones that include quantum chemical effects, bandwidth is THE bottleneck. Latency more so for short range force fields for non-reactive potentials.