There is nuance here, in the degree to which uncertainty due to lack of evidence is surfaced in scientific communications for the public.
Take for instance, the behavior of dogs. Science cannot [yet] objectively answer the question of how much the subjective qualia of a dog is comparable to the qualia of humans. What then can we say about whether dogs feel 'love'? Some might say that science has not yet answered this question; that is fine.
But others get overeager and assert that because science hasn't demonstrated that dogs feel love, the scientific position is to assume all apparent demonstrations of love from dogs are little more than elaborate food seeking behavior. This goes too far, it assumes a lack of evidence is evidence to the contrary, implicitly treating science as complete until proven otherwise. I think this overzealous sort of 'scientific' thinking reflects a dogmatic attitude which is actually antithetical to the real scientific method.
When you get to the edge of knowledge, ignoring obvious things and glossing over tends to rule the day.
Knowing what we know about people, it seems absurd to think that people just went poof, “civilization” has arrived! There were a lot fewer humans in the past, and hundreds of generations are lost to time. But the narrative of the pageant of history, often leading to the <insert nation here> greatness of today doesn’t work with “I don’t know”
https://yewtu.be/watch?v=CcXXQ6GCUb8
And if you pause to consider that emotions, particularly such core and foundational ones as love (maternal, partner, tribal) are all but certainly evolved, then existence of them or precursors in other species seems all but certain. That thought had occurred to Charles Darwin, who wrote a book on the question, The Expression of the Emotions in Man and Animals
https://en.m.wikipedia.org/wiki/Timaeus_(dialogue)
“Let me begin by observing, first of all, that nine thousand was the sum of years which had elapsed since the war which was said to have taken place between all those who dwelt outside the Pillars of Heracles and those who dwelt within them: this war I am now to describe.
Of the combatants on the one side the city of Athens was reported to have been the ruler, and to have directed the contest; the combatants on the other side were led by the kings of the islands of Atlantis,”