Earlier quoted context omitted.
I highly suspect any highly restrictive diet will have the same effect no matter the restriction. Especially if "junk food" is one of the restrictions. You hear plenty of stuff like "I went vegan, food tastes so much better now, I've lost weight, I have so much energy, my mood is better, blah blah blah." Same with "alkaline diet," "cabbage soup diet," "low inflammation diet," "bacon diet," "salad diet," "gluten free…
OP's remarkable point is that she is restricting food groups, not calories.
My mother in law also has a "I just don't eat [several random food groups]" non-calorie restricted diet as well, but the food groups are different, she says the same types of things and lost over 100 pounds and has kept it off for like seven years. Same with other people I know with omitting other random food groups.
(My mother in law actually eats outside her chosen food groups regularly, she just is really, really, really misinformed about what's in food - which further illustrates my point that it's the micromanaging and restriction, not the type of food consumed.)