> How can one dispute that Israel is a genocidal apartheid?
Let me talk specifically about the "genocidal" aspect, because Apartheid is a separate topic.
If you're coming from a place of "of course Israel is committing genocide", I don't think it very likely that I'm going to convince you otherwise. That is the "default" narrative in many circles (just like the opposite narrative also exists in many circles). That said, I'll do my best to explain why I think that claims of genocide are very wrong.
> There are literally hundreds of videos and witness testimony evidencing war crimes perpetrated by Israel.
First, there are for sure war crimes committed by Israeli soldiers. Every war crime should be condemned, investigated and prosecuted. Though I don't think there are hundreds of war crimes documented, at least not serious war crimes (serious as in causing bodily harm or death to someone).
That said, war crimes, while horrible, are an unfortunate reality that happens in almost every war. War crimes and genocide are separate things.
Genocide requires Israel intentionally trying to kill Gazans, or at least part of Gaza. That's a big accusation, and it isn't backed up, at all, by the actual actions of Israel. Israel maybe kills "too many" civilians for the amount of militants it kills (though even that is debateable), but it is targeting militants. It isn't going in there and purposefully killing civilians, for the most part, though horrible mistakes do happen all the time.
If you compare the amount of dead in Gaza to almost any modern war, there are far less dead in Gaza. And considering that Israel could do what other countries have done, which is intentionally kill civilians - the fact that there aren't more dead isn't a question of ability, but of will. Israel doesn't want to kill innocent civilians.
Most of the videos you cite are either the kinds of terrible things that happen in every war, or genuine war crimes (which do happen), or, as is often the case, an incident which looks different without having context. This is a war in an urban environment, in which Hamas is doing everything in its power to cause more Palestinian casualties, not less.
> Humanitarianaid is being held back or bombed by IDF.
This is partially true, and I'm very angry at Israel for not allowing even more aid in. But aid isn't being bombed (except for mistakes, which do unfortunately happen). And it's not accurate to blanket say "aid is being held back" - Israel lets in hundreds of aid trucks every day.
I think Israel should do a lot more, don't get me wrong, but if your impression is that literally no aid is getting in, that's very very far from reality.
> There are even mass graves being uncovered which is reported by mainstream media.
This is a story that's only a few days old. I don't think it's fair to draw conclusions on it just yet. The media has a terrible track record of taking claims against Israel at face value, only a few days later backing up the Israeli version, which often vindicates Israel. E.g. the infamous "hospital bombing" in which Israel killed 500 people, which after the fact turned out to be not even an Israel bomb, and only a few dozen died there anyway.