That's basically my lay-person's understanding also. It's because the expansion isn't significant at small scales, so gravity and electromagnetism overpower it. This causes existing objects and clouds to effectively remain the same size [I have to assume that there's an effect, stealing potential energy at very small scales].

Gravity and EM are holding our galaxy, our Laniakea, our Universe. See https://www.youtube.com/watch?v=rENyyRwxpHo .

As I understand it, the forces that keep matter together are strong enough to counteract any expansion.

Unlikely, because expansion of space is equivalent to the slowing of light, as other commenters have mentioned.

Such heuristic explanations are distractions: Locally, gravitational effects (including spatial expansion) manifest as pseudo-forces and hence can be counteracted.