High fat diet does not contribute to Gallstones formation.
At least not diet high on natural, unprocessed, healthy fats!
Low fat diet is far more likely to contribute to Gallstones formation in most people, as it slows down flow of bile, increasing chances of Gallstones formation.
Consumption of natural meat is in no way linked to gallstones formation.
Consumption of processed fats like margarine, hydrogenated fats, processed foods, processed meats is linked to gallstones and liver problems and is linked to just about any health problems, as we are not designed to eat industrial garbage.
Cows get gallstones, and consume no meat.
Several other herbivores are known to have gallstones, but consume no meat.
Generally sedentary lifestyle is linked to gallstones.
Modern Cows are sedentary. Not much running out like wild cows.
Use of artificial hormones (contraception) may also play an important role. Women are far more likely to use artificial hormones (contraception) than men, and are far more likely to get gallstones.
Women are far less physically active in comparison to men.
Food additives and not drinking enough water plays an important role.