The ICJ said no such thing. Read the ruling. It said something along the lines of the "rights of the Palestinian people to be protected from genocide and the rights of South Africa to seek this protection are plausible".
The use of the word genocide in this context is just pure propaganda. There are plenty of conflicts with significantly higher human toil where this word is not used.
And if over 30,000 dead Palestinians so far isn't enough for you, the intent is the central issue of genocide, though the Palestinian casualties will undoubtably rise.
It did not. Find me that language in the ruling. Some media said that, but not the ICJ. If the ICJ thought this was really plausible they would have ordered Israel to stop. They did not.
30,000 dead is way too much for me. Not for the Hamas apparently? For Israel going after all 40,000 Hamas combatants, is probably legitimate, as long as Hamas keeps fighting. I would so much prefer that all of the Israelis that have been killed and all of the Palestinians that have been killed still be alive.