MTL seems to be not quite such a sharp division as before, where above 1.0 was considered that, and below, sub0hming. It's more about the way the atomizer functions when you pull on it. Usually airflow, coils and wattage are somewhat different and yes, of higher resistance than 1.0 but not always, it's really more about how you inhale the vapor into your mouth. As a smoker, I would inhale the vapor into my mouth before inhaling it into my lungs. There are all sorts of available "cigarette like" atomizers, from the extremely restricted (I am thinking about the Berserker RTA, for example) to the more airy, but MTL sort of rests on the inhale side, where (many) folks used to inhale when they were smoking.
DL is like sucking through a straw into your lungs. It's not the way I smoked, and it's not the way I prefer to vape. Many people do prefer that style however, and it sort of becomes a matter of finding out what works for you, certainly many vapers are happier with lower resistances, more vapor, and a different type of draw.
Anna