Very interesting article. I think humans are very limited in their approach to what language is. Communication is more than just language - most human communication is non-verbal (facial expressions, body postures, hand gestures, general energy). Animals are similar in that regard, just with less sounds and more non-verbal bits.

Animals understand human communication. If you have a dog - that dog knows when you're sad or happy and tends to have empathy.

It may also be worth looking into telepathic communication. Certain aboriginal tribes were reportedly able to communicate without sounds and words. Then again that's not something that science could easily prove. How do you communicate modern science with someone who can't and doesn't intend to speak your language?

I think if aliens do arrive like in the film Arrival - then humans aren't ready for it yet. We're too primitive and hostile to be tolerant and learn their language. So we'd probably scare them off or attack them. Hence why they're probably not here.