I recently heard or read that adult cats don’t really vocalize much among each other as a means of communication; but that they have adapted to do so in order to communicate with humans. I don’t have much experience with feral cats, so don’t know if it’s true (?)
I only know that the domesticated cats that I’ve had have never ‘talked’ to each other through vocalization, unless it was the occasional spit/shriek in the midst of a big fight.
I can vouch that the feral cats in my neighorhood vocalize loudly and persistently during mating seasons. But it seems to happen only in the dead of night.
At one time a feral Siamese lived in the storm drain...quite strange to drive slowly and spot blues staring from the curb drains.