Is there some harm in considering Zo = 1/cC? It should only add to the
tools we have to explain electromagnetic waves.

73, Roger, W7WKB

yes. because its WRONG. you have made an assumption that is not realistic
for any transmission line. There is no way a transmission line can have a
velocity factor of 1.0, just can't happen... all the equations fall apart
and become meaningless at that point. there is a reason for the velocity
factor, or beta, depending on which you prefer. learn it, and use it
properly, and it will serve you well.