1- the European ice age eliminated almost all of the edible insects in the continent, meaning it's never been a good idea there 2- they live in and on rot and decay, and are otherwise unsanitary
We like meat from animals because it can be butchered without too much contamination. We dislike non-meaty textures- heck, I won't eat chicken feet not only because of the texture, but because what do you think chickens walk around all day in?
Sure, there's limited exceptions- pork cracklins and tripe, though most westerners also refuse to eat those as well.
The comparison to crustaceans is unfair, since most people don't eat the shells of lobsters or crabs, only the fleshy bits. Ultimately, barring some seafood and small game, we're conditioned to not eat the entire animal at once, only the parts that appeal to us. Meat on its own, guts and other soft bits in sausage, bones for broth. Eating insects invariably means that what you eat looks like what it is- an animal.
The article goes on to sing the praises of eating insects- good protein, environmentally friendly, cheap, so on and so forth. That sounds nice, but it doesn't change the appeal of eating an animal whole, or thinking about that same animal living its entire life among a pile of rotten food and poop.