So, are you saying that this is not part of the fundamental analysis you should do if you have money at stake? You have made such analysis to argue about the threshold numbers.
My only point is that >50% attacks by the people involved are purely theoretical. Attacks by almost any state are the end of your project. A billion dollars is enough to DDoS pretty much everything.
Then you argued about the bounds and if they were theoretical or not which was not the central point of the argument and we can choose another issue to illustrate our central point. I think we can argue if it is theoretical or not ad infinitum.
So, to push forward my central argument I will again say: we need to check beyond the cryptography. Not only that, I will tell you: stay tuned because a new security finding with Bitcoin will be published soon.