If I blockade you in your house, is that failure to aid? Or something else? Sanctions occur via commission, not omission. They’re not a failure to render aid or to be maximally charitable. They’re active harm.
If I decide to stop buying bread from the baker in boycott, is that a commission?
It is certainly a change of state, but the status quo does not entitle ongoing purchases. This is a sanction. I can also extend this boycott to anyone else who shops at the baker. That still is not a commission. It is a refusal to interact.
A blockade is different. It is a threat to use force for disobedience. IF I threaten to beat other who willingly shop at the baker.
Sanctions are omission, blockade is comission. These words are currently being conflated.