I’m pretty sure we don’t know that. A 400lb person will probably be healthier a year from now if they eat 1500 calories of MacDonald’s a day vs. 4000 cals of “home-cooked plant-based foods”.
Plant based diets are "good" if you are having issues with overeating/overweight and/or a diet lacking vegetables. I guess that's a lot of people, but definitely not everyone.
I switched to this because my usual post-winter diet wasn't effective, and this is.