I just have to reiterate the importance of context and expectations. If you’re getting carry-out or eating at a buffet, you’re going to get carry-out and buffet quality food. It has less to do with “Americanization” and more to do with commercialization.
Replace Chinese buffet with… Golden Corral. Would you say that the meatloaf is Americanized and thus crappy or the meatloaf is crappy because it’s mass produced and kept under a heat lamp? Why have different expectations for that Butter Chicken?
90% of the Indian food that I eat comes from the buffet, though fairly good, is clearly imperfect for a variety of reasons. The quality just isn’t the same for mass-produced food vs. made-to-order food.
Of course Americanization DOES play a role. Foods are made with less spices, peppers, etc. I know specifically with Chinese cooking, powerful spices like cloves and ginger are cut back significantly. Also the type of food: cold chicken, jellyfish, bone-in fish, that are bizarre to the American palate may be left off. However, the chicken/beef/pork dishes that you’re ordering? If you order it off the menu and it’s made to order? I would doubt that it’s much different than anything you could find in India. More expensive - granted. Tastes different? Dubious.