Consider that if a state goal was to wipe out the wealth of the other 49% as a plausibly deniable economic attack, then having a majority of the mining power within your borders makes a lot of sense.

How people think of that hypothetical if-then scenario depends a lot on numerous factors. I think, in places where corruption is more common, it is easier to believe it's less likely you'll get caught, or minimize the consequences when thinking about it. There's also a lower threshold for your imagination to go wandering off in that direction and begin architecting plans.

"If detected, could crash the whole thing" is a way of thinking more common in cultures where the rule of law is far more established in the common mindset.

I'm not making any sort of prediction (and I own bitcoin myself, though not a large amount). I'm just saying - this is how our minds work.