The thing is, everyone's body is different.

I did a keto diet with under 20 grams net carbs. 2 months, didn't lose a pound.

Not long after, I started 3x a week 75 minute aerobics class. I had already been working out regularly but nothing like a live teacher to get you to work harder.

I did not change ONE thing about my diet. I had been trying a variety of different diets to lose 10 pounds since 2003 (when I simply reduced my calorie intake to 1500 calories - totally non keto; lots of whole grains and legumes and very lenient about treats like ice cream and hi carb, hi sugar brownies) - lost 30 pounds in 3 months and effortlessly have kept it off since.

In the first 2 months of the aerobics class, lost 5 pounds and have kept it off in the 5 years since.

Exercise alone. Also able to buckle my belt at the 3rd instead of the first hole.

I know, just an anecdote but huge amounts of research back this up. Sorry, the stats on long term weight loss for keto (even though short term it's a LITTLE bit faster) are not any better than any other approach.