Young children have an innate sense of the "cosmic importance" of what they do - and what they think. At such an age, our selves and our minds are part of a larger group.
We may not be exactly aware of it, and we certainly don't know the exact scope of it (it often seems to include not just people, but other animals, nature, gods, spirits ghosts...), but we know that we are connected.
This immersion in a group mind is for both good and ill, and is just a fact of life,
There is an in-between phase or stage, in which the inner contact is no longer a spontaneous, direct, quasi-telepathic thing; but instead is sought via symbols, language, image, stories - meand to an end; methods by which people get back (partially, temporarily) that childhood state.
At this time and place of history; this is mostly or entirely lost. If people do feel connected and part of a large group, then it is not even at secondhand - via symbolic communications. The recent and current addiction to mass and social media is not about symbolic contact with a group mind, but about emotions; excitement, distraction, triggering of feelings.
The experience is apparently of isolated selves observing a display of phenomena, hoping to be stimulated.
But not entirely thus. I think there is always a sense of cosmic importance, of connection of "just being" part of something much larger - at back of people's minds, even though not-believed-in, even in these here-and-now conditions.
Such "cosmic" intuitions are nowadays publicly mocked and pitied as necessarily immature, deluded, wishful, self-aggrandizing, sad, psychotic - in a word anyone who harbours or expresses them is insane.
And, of course, they may be - especially when somebody tries to persuade and argue others into objectively accepting "his" special importance and significance on a large, even cosmic, scale!
Yet, this typically-modern way of explaining-away anything that might serve as a basis for purpose and meaning in life is altogether typical of our civilization - where is it a core element of the demonic "Project Despair".
This nihilism encompasses the whole of science (when science is taken to be a complete picture of life) as well as the workings of The System, its laws, bureaucracy, media and the rest of it.
All public and official aspects of modern life are predicated on their being no "cosmic" purpose or meaning in our personal existence.
The insanity slur is a typical modern value-inversion.
The opposite is true:
The reality is that anyone who does Not have a sense of cosmic significance is insane. That is; their thinking is necessarily incoherent. Their behaviour can be of personal and immediate significance merely - adding-up to nothing whatsoever.
I think we should regard intuitive assumptions of cosmic importance as one of those aspects of innate knowledge that were built-into us by The Creator; to serve as a necessary basis for... everything else.