In understanding the New Testament, it is useful to consider the problems that Jesus is implicitly addressing; because they significantly differ from modern awareness.
In the Fourth Gospel, the 'answers' or 'solutions' that Jesus offers imply a background of existential awareness of the implications of mortality.
In other words, Jesus offers a resurrected life everlasting of a qualitative superiority to the possibilities of mortal, earthly life; and this offer implies that it is the problem of death that is being addressed.
So, when Jesus says we need to be born again, this addresses the problem that that this mortal life is not sufficient. When he talks of heavenly water or food, and contrasts it with ordinary well water and ordinary food (and even with the manna provided by God); Jesus is assuming that people recognise that the things of this world are not sufficient, do not satisfy... because they are cut off by death.
The resurrection of the body is a vital aspect; because any afterlife which is only of the spirit (and without the body) is not an afterlife for us as our-actual-selves - because pure spirits are not-the-same as incarnated spirits.
The miracles of healing are addressing that the problem of the mortal body is sickness and age: suffering - and Jesus heals these to show that the resurrected body in the life eternal will not experience such things.
And the decisive miracle of raising Lazarus from the dead is a demonstration of what all may anticipate 'from now on' - from the time of Jesus.
The Fourth Gospel is therefore addressing the rational and true existential despair of Man when he becomes aware of the reality of mortality, with its severance of the soul from the body and no prospect of their reuniting.
This in turn implies that in the era and place of Jesus's life, such existential despair was normal and general - general enough such that it did not need to be made explicit in the Fourth Gospel. The Gospel just assumes that mortality is a huge problem for people, and that anyone who offers an answer to this problem will be welcomed.
(Welcomed so long as the answer being offered is true and real: much of the Fourth Gospel is about Jesus proving that he really is divine, hence able to fulfil his promises.)
What about nowadays, in The West? A very different situation - at least explicitly, and on the surface. Modern people claim to find sufficient meaning, at least potentially, within the scope of mortal life. Mainstream modern people do not acknowledge that the fact of mortality has the existential implications which were generally experienced at the time of Jesus; indeed, such existential awareness of the centrality of death was popular, indeed fashionable, into the middle twentieth century, among the Existentialist philosophers (Heidegger, Sartre, Colin Wilson etc.).
What, then, is the mainstream modern attitude to death? That it is something to be avoided, for as long as life is pleasant - then something to be welcomed so long as it can be achieved without suffering.
But there is a huge dishonesty at work - a mismatch between what moderns say, and how moderns behave. They say that life is sufficient; that they are satisfied to live well, die and face extinction; that to live in the residue of their actions and memories of others is enough (the fact that this obvious nonsense is so frequently and solemnly articulated is very significant).
Indeed mainstream moderns assert that it is a higher morality to embrace utter extinction; than feebly and childishly to crave eternal life like religious people do... Since modern materialist metaphysical assumptions rule-out the possibility of the spirit; such ideas can only be due to a combination of wishful thinking with some combination of ignorance, insanity and manipulative dishonesty.
So life eternal is rejected as both a possibility and hope by normal modern people; unless that eternal life were to become possible by progress in technology and medicine - in which case they would be happy to accept an eternal version of life-as-it-is - assuming disease, ageing and suffering could be eliminated from it. (This is, of course, the transhumanist project.)
Yet when it comes to behaviour (to 'revealed preferences' as economists call them); modern Western people don't really seem to appreciate life-as-it-is. The universality of sub-replacement chosen fertility is one strand of evidence; the engineering and embrace of Western population replacement by less-modern non-Western immigrants is another strand of evidence; the personal and cultural self-hatred of the intellectual and power elites is further evidence; the mass use of consciousness obliterating or numbing drugs is another thing, as is the mass scale of permanent self-mutilation by piercing, tattoos, scarifications etc.
On top of this there are the taboos against discussing death, sub-fertility, population replacement, self-mutilation... there is a significant combination of evidence that modern man is in a state of chronic and terminal despair plus evidence that this chronic and permanent despair must neither be acknowledged nor seriously discussed.
My diagnosis is thus that the modern mainstream West is In Fact afflicted by exactly the same existential dread of death and its implications as is addressed by the Fourth Gospel; but that we modern are in a deep state of denial. This denial is underpinned by materialistic metaphysical assumptions that exclude the possibility of the soul or spirit; but we also deny the existence our own metaphysical assumptions - claiming that these assumptions are not assumptions but instead rational deductions from obvious evidence...
Before the events and teachings described in the Fourth Gospel can have the effect on us that it had on the early followers of Jesus, before we can even want the gift which Jesus offered; we first need to become honestly aware of the existential implications of death.
Of course, such implications ought to be obvious, since they were known by all previous societies; and even in The West are known, at some point in their development, by all children. Nonetheless we deny them and refuse to think about them and they are excluded from public discourse.
We need to think-about death. Honestly.