Bodies are all different. Diet and exercise can work for one person and not another. But the type of person who wants to believe all fat people are slothful, all unemployed people are lazy, and so on, will invent in bad faith the straw man argument that we think diet and exercise do not work at all. They're not worth engaging with.
Incorrect. There is no person a diet and exercise won't work for. You can not run a caloric deficit and gain weight. The laws of physics apply here.
Humans are not bomb calorimeters. The physics is undeniable and straightforward, but the biology is messy and hard.
According to the nasty, nasty fights I've had with people about this topic there are, apparently, some people whose bodies are actually perpetual motion machines and I'm various kinds of insensitive for even bringing-up physics as it relates to weight. >sigh<
These must be the phenotypes the robots in The Matrix were using as fuel cells.
Are you claiming that some people are exempt from the laws of thermodynamics?