I haven't yet told you how your imagination must work. Can't double down on something I've never done.
Here you did:
You can imagine it, sure, but you are twisting it into a pretzel that it really isn't in order to imagine it that way.
Nope! My imagination works without pretzel-twisting.
Sure, but that doesn't make it simultaneous, because the rigid structure is always going to be present in combat regardless of what I do. Short of completely re-writing how combat works anyway.
The rigid structure is for the players. The characters are not experiencing everything broken up into turns and rounds. The idea that the person who counters the counterspell is doing so after the fact is due to your insistence on viewing the actions as rigidly chronological. But you simply don't need to do that.
If you prefer it, then by all means go ahead and treat it that way. But don't expect others to accept the limits you've chosen.
Within its own reality, yes - or at least it's trying to.
What I was addressing was that Max said my imagination was wrong if I imagined the moon hitting the earth and then looked out the window to find that it had not happened. In other words, that for an imagination to be "right", its contents must be fact.
Which is staggeringly off-base. It was an attempt at a counter point that pretty much reached critical mass, became a black hole, and sucked all logic into it. It made me have to lay down for a bit.
My point was not in any way about any attempt at verisimilitude or whatever you're aiming at here.
That by the time the second counterspeller realizes the first counter is being cast* and can get her own away, it's already too late.
* - as opposed to any other reaction-speed spell that she wouldn't counter.
Who says? Clearly the rules do not say that. It's AN interpretation, not THE interpretation.
Why should the second counterspell always be faster than the first, though?
Maybe it's not. Maybe the second counterspeller realized what the first was up to and was ready. Imagine for a moment that this was happening in a book or a movie instead of a game. No one would have a problem with it.
Have you ever stood up in a movie theater and said "wait that wizard just went out of turn"? I mean... I have, but it was at "The Notebook" and I was on mushrooms, so in my case it made sense. But any other time, it'd be a silly thing to say.
You and
@Maxperson are applying the game structure to the fiction. Just don't do that for a moment and then there's any number of ways to say it would work as it plays.