It absolutely is. It is now known, for sure, what happens when two WDW monorails collide. It is also now known, for sure, what happens to any occupants of the cone when that happens. Should that ever happen again, with a guest inside, the nearest surviving relative would surely be able to win a lawsuit big enough to get themselves a seat on the board of directors if they want one. The plaintiff's lawyer pretty much just has to bring in a big, blown-up, high-resolution shot of those monorails sandwiched on top of one another, and the case is signed, sealed, and delivered.
Sure they could. But I don't think they will. That's not a comment on the likelihood of another accident, or the "risk" to any passenger. I agree that the chances that it might happen again are vanishingly small. Indeed, the chances that a meteor comes screaming down through the sky and kills a guest sitting in the nosecone might well be higher. But, this isn't about what "is likely to happen". It's about the liability risk to the company if something *does* happen. The payout if something does happen would be so astronomical that there's just no way that the risk management guys will ever sign off on a guest in the nosecone of a WDW monorail again, especially in light of the fact that the benefits of letting guests ride there are infinitesimal. Indeed, I can't even imagine Operations asking them to reconsider. What's the benefit to them? Next to nothing.
I could be wrong---it wouldn't be the first time---but I don't think so. Time will tell.