I started losing weight once I found out that pizza is measured in slices.
No diet per se. Just portion control, eliminating added starches and eliminating 'carb snacking'. Some of this isn't easy for someone who loves italian and spanish food. Lots of green salads. Increased exercise , whatever I can squeeze into my schedule. Mostly cycling, a little bit of running, some swimming (somewhat hampered by covid), some weights and body weight exercises. If I am disciplined on both eating and exercise, I keep my weight and can afford to have a slice of cake or a coke. If I slack off, the pounds start creeping back up. There is no magic involved.
As for the role of different diets. Yes, you can turn yourself into the 4.5lb feed / lb of bacon hog by changing your diet away from carbs towards protein. You are just reducing your ability of turning calories into bacon. Doing so will increase the amount you can over-eat relative to your total caloric expenditure.
But no matter how hard you try, you will not gain weight if your caloric intake is below your daily energy expenditure for a prolonged period of time. No matter what your 'metabolism', you are never going to beat the 2.8lb of feed hog. Anything else would require nuclear energy. Most of the people who 'gain weight on a 1600 calorie diet' somehow forget to record some meals or make 'errors' when accounting for ingredients.