"insight" typically is a short-hand way of saying "insight into the true nature of Reality" or "insight into the true nature of our situation"
So if insight (by meditating on selflessness, for example) leads one to see definitively, directly, and intuitively that there is no separate self, then the aims of the many and the aims of the nominal "individual" are seen as overlapping to say the least.
So what's the real condition?
In a sentence, all sentient beings want happiness / freedom from suffering. They don't wish to suffer, they wish to be happy.
Insight can lead to an experiential understanding of this, which is where insight into selflessness of all dharmas yields its fruit so-to-speak.
Selflessness can be demonstrated by various shapes of reasoning. The computer monitor you see is not really "a computer monitor" because it's made of many separate parts. Each part is itself not a computer monitor, you have the shell, the screen, the stand, the cable. The shell is not a monitor, the stand is not a monitor, etc. So where is the monitor?
Similarly, we can apply this clear and logical reasoning to a separate, independent, lasting self and see that truly no phenomenon has self-ity. Some might jump to the conclusion and say "well then everything is one!" but that is also excess talk. One is a word that comes up in dependence on the concept of Many and, therefore as dependent upon each other, neither one exists nor not-exists in the middle free of extremes.
The logical part must always be supported by and footed in the understanding that we don't want to suffer. From the largest man to the smallest insect, from the whales to the birds, all beings are day-and-night avoiding pain (or perceived pain) and working toward happiness (or the skewed cultural reinforcement of what happiness should look like).
Insight into the situation gives us compassion, which is a fundamental aspect of clarity. Much like a person watching the inner workings of a clock, when we see the cyclic functioning of samsara, we feel for the beings who are trapped in unwholesome cycles. Furthermore, the only separation between us and other beings is really just our karmic histories/trajectories. Had we accomplished the same deeds and thoughts as other beings we would be on their exact paths, and thus knowing that we could just as easily be in switched places with others is another key element in understanding selflessness, which in turn gives the incipient awareness of true compassion.
Compassion (yearning for and acting for the end of all beings' sufferings) and Wisdom (that realizes emptiness) are what makes a Buddha.