That's the theory and in this sense so you are right.
But antennas are more complex devices. If the real wold works as the simplified theory says you should be able to compensate a small antenna with a simple signal amplifier.
Unfortunately does not works because the amplifier do not impact on the noise/signal ratio. That's the problem we have with short antenna in both receiving and transmitting.
Anyway we are not considering the LoRa spread spectrum technology that can impact on both theory and real world experience.So, at the end you could be right. And I hope that.