Check out their research. It's very solid - there are all sorts of conditioned response tricks to see on social media, but the UCSD research has recorded examples of multiple pets using the same untrained behavior where they string together 2 or more words to indicate a new idea. Not only are the pets talking, but there are emergent and convergent abilities being documented that demonstrates a common mode of cognition that arises from the underlying cognitive capacity of these animals, across species.
There's a great example of a dog on youtube where it used "squeaky car" to point out a firetruck with the sirens going. There are examples of dogs "laughing" at farts, calling out smells, telling owners about injuries or burrs stuck in paws, discomfort or pain in a leg or stomach or ear, and so forth. They indicate affection, anger, impatience, happiness, fear, confusion. They identify group membership - stranger, family, neighbor, friend, human, animal, dog, etc.
Video examples on YouTube are ubiquitous at this point - take a look at the training methods, the way vocabulary is modeled and taught, and then go in with a skeptical perspective. For those owners that follow the teaching methodology validated by the UCSD research, they're providing their animals with a legitimate skillset that empowers the pet with language understanding, the ability to communicate and creatively produce novel and complex ideas.
This shouldn't be too surprising - based on neuroscience research, it looks like the engine of human cognition is the mammalian neocortex. Lions, tigers, and bears (and dogs, cats, whales, primates, and nearly all mammals) are likely able to use language, given the apparatus and training to do so. Humans have a unique capacity for complex vocalization and extremely sophisticated culture, allowing rapid uptake of language skills. Given the opportunity, it looks likely that nearly all mammals will have some facility with language, simply because the neocortex function is so powerful and plastic.
I’ve seen some BilliSpeaks videos that absolutely convince me cats have more language capabilities than previously thought.
When you say “convincing” what are you looking for? Do you think these youtubers are just using editing tricks and traps to convince a gullible internet? Genuinely curious.
Cats don't talk in complex ways to owners. Listen to what a male cat vocalizing while trying to woo a female cat. They have something to say and a means to say it. They don't need that kind of communication for reminding the food dispenser what time it is.
