This is definitionally wrong. Sentient merely means "having sensations" or even the weaker having "senses". Perhaps you mean "sapient", with reasoning, self-knowledge, and an "internal life".
This too would be wrong, but not as obviously so. When we actually try to look and measure other animals fairly, we generally find that in measures of cognitive capability, there are animals that are not that different from humans. Many animals pass the mirror test. There are birds with complex vocal languages. Both apes and birds have been recorded spreading adaptions in food preparation within a cohort and down generations (the two astounding cases are dealing with the toxic backs of cane-toads in Australia -- learning to flip them over and only eat through the stomach (corvids) and picking them up and washing them (ibises)).
You also have the opposite problem, where things we think we're good at, even ones some would say define us as a species, are actually pretty poorly done by many of us. GPT-2, which is clearly not sapient, and only capable of writing a terrible, meandering essay, still does better than many high-school students, or even college students. And we now have much better examples, that still clearly aren't sapient.