Crows speak to one another, sometimes about us. They warn each other about humans who are not kind to crows. Prairie dogs have different calls for different predators, and functional “adjectives” to describe them. Dolphins communicate with one another through tissue vibration, much like vocal humans.
Social animals communicate; it’s what we do. And I don’t think it can be argued that crows have a “better” language than dolphins, or that dolphins have a “better” language than prairie dogs. Each language works for the animals who “speak” it.
Likewise I don’t think human languages – verbal or non-verbal – are necessarily “better” than each other. I think Each language has the potential to communicate – if only speaker and receiver can both understand one another.
Many people have difficulty with vocal speech, but they absolutely communicate. Whether that’s through gestures or written text or a text-to-speech communication device or sign language or grunts, people communicate. If someone is limited in their ability to communicate in a variety of ways, meet them more than half way and learn how to communicate their way.