The lack of comprehension of fundamental physics on this newsgroup is
astounding, so it's no surprise that a less-known fact has been missed:

A superconductor has zero resistance only at DC. The resistance at RF
depends, among other things, the frequency and the material's
temperature. Because the resistivity of copper drops dramatically at
cryogenic temperatures, it can be difficult to make a superconductor
with resistance as low as copper at the same temperature.

Very small superconducting antennas have been demonstrated, but they
still have a very large near field which sustains loss by coupling to
nearby objects, and a large reactance which necessitates potentially
lossy matching networks.

Roy Lewallen, W7EL