First off, that’s a well reasoned answer and the truth is that no one knows how exactly a mining attack will play out. There are many variations of an attack, who the possible perpetrators might be, how easily repeatable it may be and they’ll all factor into responses from the other camps in the bitcoin community. I see Bitcoin as a 4 legged table with these factions: miners, users, devs, business. In a mining attack where there is a persistent threat from a highly resourceful entity that wishes to harm Bitcoin, the other 3 factions will have almost no choice but to hit the reset button on the proof of work and to unfortunately punish all miners.
I’ve also recently started to believe that a 2nd voting layer using PoS (in addtion to PoW) could be used to mitigate large mining attacks. An altcoin, Decred, is testing this idea and it’s possible that Bitcoin could adopt defenses such as these.