JB writes:

You are absolutely wrong on this. In some cases, dead wrong.
External distractions (real life turbulence, watching the restricted
airspace around you, overlapping ATC comms, other planes buzzing all
around etc etc etc) can turn a decent student pilot into a panicked
ball of jelly wondering how he will clean up his pants if/when he
lands safely.

Following your logic, any distraction can do this, which means that no amount
of simulation OR real-life experience can be of any use, since there will
always be unexperienced distractions waiting to cause trouble.

But if all distractions are not qualitatively unique, then a single
distraction of any kind will suffice to simulate all others, in which case
both simulation and real-world experience will suffice as well, without
running the entire (infinite) gamut of possible distractions.

When ATC talks, you can get so flustered that you don't
know what they said. Been there, done that. That will never, ever,
ever happen to you sitting at the monitor killing time before Sesame
Street comes on.

It happens in simulation all the time, just like real life.