I think even if you have volume factored in like photogrammetry/lidar, the inside of the food could be something else too like a chunk of meat inside potatoes
Steelmanning this: You take your phone out and snap a picture and it gets added to a running total without typing into a tiny keyboard or doing any math. You consult your total next time you're thinking of eating.
Critiquing: You still need to figure out serving sizes - it's going to need to ask how many servings. Nutrition labels also aren't available for any number of things.
Any other interpretive situation based solely on a camera has so many inherent flaws as to render this almost useless.