They may have done so because this chapter of the conflict is now in its fourth month, and as with most wars, there’s a gradual loss of public interest over time. Same situation happened in the Russia-Ukraine war.
The ICJ ruling itself didn’t seem to have any teeth since there was no clear ruling on genocide (beyond "please don't do it in the future"), which was the entire purpose of the case in the first place. All it did is is order Israel to "take steps to avoid genocide in Gaza". Beyond that, it didn't even call for a ceasefire (never mind that Israel would likely ignore the opinion of any UN related body anyway). Another reason the South Africans brought the case was to curb Israeli fighting in Gaza. It didn't do that either. So all things said, we are back to square one, where only Israel & Hamas, by way of the US, Egypt, and Qatar have any influence actually agreeing to a temporary ceasefire by way of returning the hostages and releasing Palestinians held by Israelis.