Is that especially simpler than e.g. an attack on the above ground cabling systems by firing carbon fibre conducting wires over them, as the US is said to have done in the Iraq war? Not that I don't think underwater drones are a future risk, but the belief its a risk which can't be mitigated, or a worse risk than ones which exist onshore, seems a bit weak.

But none the less, yes. This would be a risk. Perhaps one which demands better drone detection and defence systems around wind turbines and O&G fields?

Say that it is .. it's still hard to near simultaneously take out all wind generators than to mass swarm (with a smaller number) a single platform, well head grouping, or onshore processing facility.

Recall the context - a field of many wind generators Vs one or two platforms in order to "take down" a state's power grid.

Ropes are strong because of many strands.

That would seem like either an excellent way to start a new war, or a galactically stupid way to try to end one.