If Israel did not partake in any activities, there was no need to tell them not to. The ICJ could have unequivocally absolved Israel. They did not do that. They found merit in South Africa's accusation, and there is documented, video proof of both incitement to genocide and proof of activities that amount to genocide.
Remember genocide is not just killing people. Per the official definition it is genocide if
one or more of the following actions are committed
with the intent to destroy, in whole or in part, a national, ethnic, racial, or religious group
Are Palestinians a people of a specific national origin?:
Yes
Are Palestinians an ethnic, racial and religious group?:
Yes.
Is there intent to destroy? -
Yes
Proof/Example1:
https://www.reuters.com/world/middl...ge-an-incitement-violence-us-says-2023-03-01/
Proof/Example2:
- Killing members of the group - Yes Israel has killed Palestinians.
- Causing serious bodily or mental harm to members of the group - Yes, Israel has wounded more than 60K people just in this war alone. They further psychologically torture Palestinians even in the west bank by conducting middle of the night raids on houses for no reason. Further they imprison and torture children including threats of sexual violence.
- Deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part - Yes, by cutting off power, water, food, Israel has inflicted conditions on life that will bring about their physical destruction.
- Imposing measures intended to prevent births within the group - No evidence of this.
- Forcibly transferring children of the group to another group - No evidence of this.
Remember, for it to be genocide not all conditions have to be met per the official definition. There has to be intent, and one of those 5 points have to be true. This is the case with Israel. Hence guilty of genocide.