All your links don't show any
"concrete" evidence of a16z failing to pull out and being at a huge loss from their
"crypto" investments.
The web3 bullshit that they are spreading as mentioned in your article is evidence that they are pumping their own bags and continuing to hype the web3 narrative with their nonsense. But it isn't evidence that they are 'not securing the bag' and just only sitting there in the bubble, nor does it show that they are at a significant loss. They aren't that silly enough to just sit around, hold and not secure the bag in their investments.
They (a16z) made it so that in their own crypto investments, they can't lose unless in rare circumstances, even in the event of a hack.