Solzhenitsyn famously, and accurately, stated that the root of the problem of our time and culture is that Men Have Forgotten God. This is just a fact - but when Men have indeed forgotten God, then that fact is invisible to them, because their thinking has become incoherent as a consequence.
I know this from both side, because I was an atheist from most of my life; and I know that my thinking was intractably incoherent. I even knew it at the time. Being an honest person, my life was a sequence of attempts to find some kind of basis for morality, art and science - and the sequential discovery that I could not find any such basis.
Socialism, liberalism (social democracy), environmentalism, Small-is-Beautiful distributism, anarchism, conservatism, libertarianism, pragmatism - trying to be apolitical... I was interested by many (non-God) spiritualities at different times. I was sometimes Establishment, other times bohemian. I kept seeking and changing, because - when pushed - nothing made any sense.
My profoundest intuitions were therefore in continual danger of erosion - because if one's fundamental convictions are false and incoherent, then one becomes a victim of circumstance, and convictions can drift open-endedly - in practice, nearly always in the direction of mainstream social norms; because - why not?
Because Men have forgotten God - are all sorts of incoherent nonsense has become mainstream - and what is mainstream has become mandatory - because why not? Indeed nearly everything pushed by the mass media, politics, the bureaucracy, the churches and charities is not so much wrong as incoherent nonsense.
What can people who have forgotten God do when incoherent nonsense (e.g. feminism, antiracism, multiculturalism) is pushed at them, when they can make no sense of the world and of their lives? When self-contradiction is built-into law and enforced by employers.
When every organisation and institution, everywhere, is corrupting and collapsing; but collapse and corruption is celebrated as a A Good Thing. Destruction and chaos are relabelled creative diversity - because when God is forgotten there is no difference.
Without God there is no purpose, without purpose there is no meaning - so obviously nothing makes sense; obviously nothing ever can make sense.
Yet, as children of God, we cannot help but look for purpose and meaning - we cannot help seeking, but by denying God we have ensured in advance that our search will certainly be fruitless. Any truth, beauty, moral conviction; any meaning or purpose we think we have found in one place - will certainly be contradicted by those we find in other places - because there is nothing to hold it all together.
Modern Man - each and individually, has chosen to assume that God is not and never was, so all is mechanical; and it has both made him mad and unable to detect his own madness.
Every individual is equipped with what he needs to know God, discern purpose and find meaning in Life. When he does not do this, but instead bases his existence upon a denial of coherence, then he has only himself to blame.
Modern Man - one at a time, person by person, each in his freedom and responsibility - is insisting that life is nonsense; and finds confirmation of this assumption everywhere he looks and whatever happens.
If insane incoherent nonsense is what Modern Man wants, that is exactly what he will get.
Note - What we have is insane incoherent nonsense. Nonsense can be coherent - like the world of Lewis Carroll; insanity can be coherent - with systematic delusions; incoherence can be sane - like that of the unintelligent and uninformed. We have them all together and at once. Because without God - why not?
Further note: I think that a big problem among modern people is that they expect nihilism passively to be 'solved for them', without activity on their part, without decision, without choice, without the exercise of free agency. Indeed, for modern Man it is a measure of authenticity when life irresisitibly imposes itself upon us - whether we like it or not. But, for modern man - with his high level of self-awareness - that rules-out any answer; thus the path of attempting to extinguish consciousness by numbing with distractions or immersion in virtual reality media; or intoxication with drugs/ sex and other overpowering stimuli.