Because the reality is that you can find tacos and food items of many variations in Mexico (or wherever) that the people there will call a taco, and they'll do it without any of the sort of snobbery you find in these comments.
Like, tacos are a single ingredient food item? Then why can I find people slopping on any number of side items down the street in Guadalajara? And it's still labeled a taco? They really need to read HN and become illuminated. They're wrong.
Frankly, the idea that Mexican cuisine (or whichever cuisine) was frozen in some snapshot back in history—and anything they do eat since then is "incorrect"—does more to erase reality than pointing out that maybe the cuisine is much more varied than someone on HN thinks.
And all of this is said before even getting into regional variations like what happens to cuisines once they cross borders into different cultures. Americans eat hard-shell tacos? It's a lot more interesting to me to explore why that is than to roll our eyes at how people are ugh doing it wrong. Maybe artifacts of one culture changing when they enter other cultures is the beauty of culture rather something that needs to be corrected.
I think this is because Americans feel big-brotherly protective (in a creepy way) about their Latin American communities.
Altered versions of e.g. Italian food (e.g. pasta carbonara with cream, deep dish pizza, submarine sandwiches, chicken parmesan), Japanese food (California roll, Philadelphia roll), Chinese food (fortune cookies, General Tso's chicken, beef and broccoli) don't cause similar reactions.
Like hell they don't! Most of your examples are just ignorable new inventions, but the reinterpretation of spaghetti carbonara (not pasta carbonara, you heathen) as a shitty cream sauce? I'll go to the mat to decry that horrendously disgusting perversion.
Anyone that prefers that hot mess probably also puts ranch dressing on everything, including pizza, and thinks Velveeta "queso" is delicious.
https://reluctantentertainer.com/buttermilk-pancake-pigs-in-...
https://www.texascooking.com/recipes/sausage-bundt-cake.htm
https://newfoundland.ws/christmas-old-time-pork-cake-recipe/
Referring to the Finnish variety or other ?
Kolaches mean different things in different parts of the U.S.
In Chicago, they're often filled with sweet things, and sold by mom-and-pop shops and bakeries.
In Houston, they're mainly for breakfast, with things like eggs, bacon, sausage, brisket, etc. and sold by chains like Shipley's and Kolache Factory: https://kolachefactory.com
Recently, the Houston version of kolaches has made inroads into Chicago: https://www.howdykolache.com
https://en.m.wikipedia.org/wiki/Pączki
Paczki Day is almost as big a holiday in Chicago as Casimir Pulaski Day.