Actually, no. Look up videos of "range-gated imagers". With multi-hit data for each scan point and appropriate processing, you can see through fog. This technology has been around for years but not talked about much outside military applications.

Thanks for that, it makes sense. Same techniques are available in radar. This will give you a higher noise floor and also lower signal if fog sits between you and the subject. It probably does improve the situation over visible light, but only up to a point.

Agreed, thus the need for radar. Thermal imaging can also see past fog fwiw, though it has other tradeoffs.