Additionally they werent charged on the basis of unporportionality afaik, i think all the charges are based around failing to let in enough food aid, causing a famine.
No, starvation is only one of the alleged offences: "the use of starvation as a method of warfare, together with other attacks and collective punishment against the civilian population of Gaza"
https://www.icc-cpi.int/news/statement-icc-prosecutor-karim-...
> The Prosecutor seeks arrest warrants against Benjamin Netanyahu, the Prime Minister of Israel, and Yoav Gallant, the Israeli Minister of Defense, on the basis that they committed the war crime of ‘intentionally using starvation of civilians as a method of warfare’ under article 8(2)(b)(xxv) of the ICC Statute. The Prosecutor also seeks to charge the two suspects with various other war crimes and crimes against humanity associated with the use of starvation of civilians as a method of warfare under articles 7 and 8 of the ICC Statute
Even in the latter case, the cost to civilian lives has to be proportional to the the military value/lives saved long-term by ending the threat. This is not proportional: https://www.972mag.com/lavender-ai-israeli-army-gaza/
But unfortunately, the latter case does not account for all that we've seen in the last few months and years. There's been plenty of "targeting civilians" too