Is this really a property of ICOs? the behavior you describe may be very common nowadays, but from what I understand there is nothing intrinsic in this kind of funding model to be necessarily like that. Maybe after a crash the market will get a bit more mature and start using public ICOs for real stuff, and I think that could evolve into something really interesting :)
This case sounds like #3 - where they have an idea, but immature company structure, poor legal structure, and no governance that is supposed to bind a team together - in this case they are fighting about the money ...
As always - in the end it's all people. Public ICO is a tool, and it's really NOT the tool to use if you want to find a real base of support and well-intentioned stakeholders (who won't turn around and sue you the moment the ico completes :)
One hostile contributor doesn't tell you anything about the intentions of the rest.
There are a ton of ways to find and secure proper, reliable stakeholders who are committed to your technology or your cause/product. (Private ICO being one of the ways. Keep things under wrap, develop the technology, have a proof of concept, sell some product, and then MAYBE if it makes sense, go public.) A public ICO blasting across the internet when there is no product, no plan, and no real engineering already done is nothing but a cash grab, and I am not at all surprised that they are embroiled in lawsuits.