More specifically, it's already cooked.

In fact, 8 oz of hot water (say from a coffee shop or not quite boiled on a camping μstove) added to a larger cup, covered, will rehydrate pasta without external heat just fine (~15 min) and it's probably not as sodium-terrible as ramen.

Ramen doesn't need to be sodium terrible. Even with cheap Top Ramen and similar, you don't need to use the entire "flavor packet", the noodles themselves (which are all you're interested in for the calories) are low in sodium.

Even ages ago when Top Ramen was a staple of my diet, I found it much too salty to use the entire flavor packet.

I use a wide mouth, vacuum bottle, to cook rice or pasta. It keeps the heat in, so you only have to heat it up initially, not continuously. A bonus is that you don't have to pay any attention while cooking,