writes:

When I asked you if you had ever filled out a flight planning sheet, you
replied that you had not because there would be no one to file it with
anyway.

And there isn't (apart from a basic flight plan for VATSIM flights), for
flight simulation. So there is no error in this.

That means you have no clue that "flight plan" refers to two things:

1. A detailed plan for the flight.

2. An abbreviated summary of the detailed plan filed with the FAA.

I'm aware of both, but the facts above remain correct.

All real pilots do number 1 for all flights (other than the obvious such
as practice in the pattern) including VFR flights.

Not true. Many private pilots are exceedingly casual about flight planning.
This doesn't necessarily lead to accidents, but in many accidents, a lack of
proper planning is a contributing factor.

These days most people use a computer based flight planning program and
generate the sheets automattically, but all real pilots know how to fill
one out by hand with pencil, paper, and real charts.

What they know how to do when tested, and what they do in the real world when
flying, are not always the same things.

That's what real pilots are REQUIRED to do to meet the requiements
of 91.103.

There are a lot of things that private pilots are required to do that some of
them don't actually do in practice. The FAA has no way of enforcing these
requirements unless something happens during a flight.