That's where you're wrong.
First, #Bitcoin is and always will be CPU, GPU mineable so honest users can support it in time of an attack too.
Second, 51% attack means rewritten one block. That's far from game over.
Discussion
Yes, but CPUs and GPUs are hardly competition to those attacking with ASICs. What percentage of Bitcoin is mined using ASICs? Probably 99.9%
ASIC short supply means you can't easily or quickly recruit more ASICs for honest users to fight back.
And about the video, AA is great, but it assumes a rational economic actor. States don't give af about that. They can throw other peoples money at the attack indefinitely.