It's about 5% the first and 95% the second, sadly. The well-connected VCs pretty much know what the outcomes and the valuations are going to be in advance. The less connected ones get burned by adverse selection and lose money.

So a bootstrapped startup cannot ignore the VC realm regardless, especially once it is time to come to market.

That I'm not as sure about. You just have to bootstrap into something that VCs aren't likely to be interested in, and get enough of an early lead and enough good will that they can't just make a competitor out of nothing should their interests change. It's quite possible, as far as I've seen. Bootstrapping is far harder than it should be (in part, because the American middle class is dying and no one has any fucking money) but I don't think that the VCs are the cause of that.