Art wrote:
"Any thoughts as to why it sgould be so and the scientific facts to
support it?"

We have plumb lines and bubble levels which allow easy determination of
vertical and horizontal directions.

We often inhabit a nearly horizontal plane

If we are as likely as not to communicate with any particular direction,
an omidirectional vertical antenna makes sense. An inclined wire would
favor some direction to the detriment of another. Sure a slopimg wire
works but doesn`t reach maximum height or length as effectively as a
vertical or horizontal wire would.

Why a straight dipole and not a V-shaped element? The V-shape corrupts
the nulls at the ends of the straight wire.

Vertical and horizontal antennas are not solely accidents of history.

Best regards, Richard Harrison, KB5WZI