Why is it so easy to tell the difference between live and recorded music?

Dynamic range certainly plays a huge role.

I also notice the ability of many a system to start and stop fails to mirror reality, even as some claim the superiority of their means of implementation.

But for me, I'm MOST bothered by the incorrect tone / timbre of most high-end audio systems, even when they possess notable dynamic range or speed.  There's simply an unnatural sonic signature to most high-end audio components / systems I encounter.  I cannot get past that

Some of Frank Zappa's stuff is very hard to tell if it is live or not. Mostly very well done.

Frank Zappa’s entire catalogue or most of it has one outstanding characteristic. Dynamic range. The Official Dynamic Range Database. Check it out.

I posted about this a while ago.  To my ears, there is very rarely a doubt.  Sight unseen, approaching an area where music is being played, without prior knowledge, I can very reliably tell if "it's live or if it's Memorex";-)

I've always thought that, on a subconscious level, your brain goes down its "survival checklist" when it encounters new sounds. One of the questions it asks: Is what I'm hearing able to cause physical harm? Is it real? Is it close? Etc. A marching band passing your open window leaves no doubt as to its potential for physical harm. Any stereo you are likely hear just won't have the same cues.