No. You simply have intentionally describe thing in nonsensical manner. I don't know why, the game certainly doesn't demand this. "This 120 foot long dragon occupies this 20 foot square" is a thing that a person can say. It however is not a thing that can be visualised, because it is logically impossible. Personally I wouldn't consider making things intentionally unvisualisable good GMing practice.
The game says that the 120' dragon fits in a 20'x20' square. I dunno what to tell you, that's what the game says. If you think it's poor GMing to use what the game says, I'd say you really need to send a letter to WotC about this. In the meantime, maybe don't tell other people they're bad GMs because they don't do it like you do?
No mate. The mammoth example was brought up because you thought that it would be more realistic for giant lizards to be able to bring down the modern world full of tanks and supersonic jetfighters than a group of late medieval people killing said giant lizard. This of course is blatantly laughable. It was never claimed that dragons are as easy to kill than mammoths, merely an example that it is possible for humans to kill animals far larger than themselves even using simple sticks. One would expect renaissance tech help quite a bit, and of course with modern tech it is not worth even contemplating.
Um, no, and we can all scroll back up and see where mammoths entered the discussion. And yes, Reign of Fire is MORE REALISTIC than D&D fighters going toe-to-toe with dragons. At what point does this claim that it's very, kinda or even sort realistic? It's MORE realistic that the silliness that D&D does. As in, Duck Tales is MORE realistic than, say, Road Runner.
This again is not what happened. I had mentioned before the t-rex size was examined that I'd expect dragon extremities overhanging their square. So I was using a consistent model the whole time.
"A bit." You said, specifically, overhangs "a bit." Your image now is 50% overhang. As in, the Dragon in your image is more than 60' long but fits in a 40' space. I wouldn't classify that as "a bit."
How do you think the reach works? The dragon can attack a foe 15 feet away without leaving its square, because it's neck and tail can reach that far away.
I dunno, doesn't really make much sense because you're only that big in the instant you attack, and that size has no other meaning. I can't ready an attack outside my reach for you to attack from yours, for instance. That extra size exists only to enable the reach mechanic, and not to describe the fiction. The fiction you're using to describe how reach works is post-hoc -- it comes after you see the rules and need to find a way to rationalize them.
Like I have said several times, I'm fine with pretty broad strokes simulation. Just some basic sensemakery is fine. And yeah, I'd prefer 5e to have a tad more of it. But I don't think what is gained by being intentionally obtuse and interpreting things that actually make sense in nonsensical manner.
I didn't start the argument that dragons are just fine simulation. I started with they are not. You've argued the point. If you didn't mean to argue that point, what are we doing?
You have several time misinterpreted what has been said and when, in order to attack some strawman version of my arguments. Call it what you want, but stop doing it.
Can you point out the specific misinterpretations? That way I can be sure to avoid those, as asked, instead of having to guess what it is you mean. I've taken the time to lay out the sequence twice, so it should be fairly easy.