For sure. Looking at calories is only one part of the picture but
the quality of the calories you consume are more important.
Absolutely. I love how the RDA is a blanket number, as if the average 5'8" sexagenarian needs as many calories as an active 6'3" 25-year-old male.
If anything, the FDA (and relevant bodies) should be promoting the Mifflin-St. Jeor or Harris-Benedict equations, both which are vastly more accurate than the one-size-fits-all value that is currently being touted today.
I have a friend who is in his early thirties, is thin and you would think he's very average by anyone's standards but was complaining about a lack of energy so he went to see a doctor. The doctor ran some tests and asked him what his diet was. Turns out that he ate McDonald's almost daily; the doctor ordered him to stop immediately because he was at a high risk of having a heart attack. Although he was visibly thin, his organs were covered with a high concentration of visceral fat.
What you can't see is often what is most dangerous. Do you know how much visceral fat you carry on you? I bode you no ill will but please don't fall under the illusion that because you can't see something it's not there. Visceral fat is as dangerous as cancer in that regard.