This is similar to what I have read when someone comes into a health section on say a general forum for cars or some random hobby. The people who frequent it are usually the people who lift not tri people or even just runners or cardio people at all. So for example someone will post a thread I want to lose weight… the first response will be no you don’t want to lose weight you want to gain muscle and lose fat your current weight is fine (being said of course without knowing the persons weight so may or may not be true). The mentality in the body building and power lifting areas of training are completely different then what the average person wants let alone someone doing endurance sports.
Then this person responds with ok I want to burn fat, I don’t want to get bulky, so I should just do cardio. They then come back with more muscle burns more calories just lift. There is logic there, increased muscle mass does mean that you will burn more calories just sitting around on the couch so they are no entirely wrong. However it ignores that someone coming in who needs to drop 30lbs in BF is not going to be doing an hour of lifting so a gym session of lifting may burn 200 calories vs 500 doing some cardio. Yes they will eventually gain muscle to increase ability to burn that fat, but in the short term the cardio will probably be more beneficial… along with some weight training.
The other side with the cardio makes you fat, which isn’t correct but has some truth to it because people are stupid. They go do an hour of cardio with little effort burn 500 calories but think they burned 1500, they then reward themselves with a 1000 calorie smoothie. The net result is that they consumed more calories. So again this is not an issue with the cardio but an issue with the person.
My guess is that is where all this is actually coming from just not being put forward in a logical way, kind of a not wrong but not right either situation. There is no point in body building and tri people to take advice like this from each other.
Personally I do understand the concept/confusion of cardio not resulting in much weight loss, I know this is hard for many here to grasp but some of us do build muscle without trying even doing SBR. It is very difficult for me to lose overall body mass as I seem to gain muscle at the same rate I lose fat unless I cut calories to the point that it just isn’t healthy.