I think the 6lb figure is the average people gain over “the holidays”, that is between Thanksgiving and New Year.
Personally I’ve been on a not too strict low carb diet for about six months, 10-20 grams of carbs a day. I’ve consistently lost about a pound a week, 30 lbs total so far. Not that hard, but I’ll go ahead and eat some on a holiday, just not the whole month. I had stuffing and pumpkin pie on Thanksgiving. Funny thing is I couldn’t even finish one piece of pie, it just tasted too sweet.
10 to 20 carbs per day is very low carb. You can eat 50 - 100 carbs per day, and still lose weight, just not as quickly. And if you stick to 50, you can still keep your blood sugar under control.
I started out on keto and stayed around 20 carbs per day, but now I’m just more relaxed about it. If we go out to eat, I order whatever I want, then go back to my diet the next day. And we eat out about once a week. Just cleaned out my closet, and gave away 2, 33 gallon bags of clothes that are too big for me, to goodwill. Best diet ever!