Modern sexuality has it that nothing is more important, more fundamental, than that a person should be able to express whatever sex and sexuality they happen to wish - in their current mood, here and now, feeling as they happen to feel just at present.
In sum: the assumption is that, when it comes to sex and sexuality - like a stereotypical hysterical prima donna - whim is iron.
In other words, modern sexuality has it that current expediency is profound; such that to thwart sexual whim is hatred, aggression, oppression.
Which means - in practice, and given that people change, develop, are corrupted and repent - that everyone is supposed to pretend that whim is not whim.
Yet, as well as being the most important thing in the world, such that even to challenge or attempt to correct a currently-declared sexual desire or identity is utterly intolerable; modern sexuality also insists that sex and sexuality don't really matter.
Indeed, to emphasise that sexuality is a fundamental aspect of individual, social and political life - and therefore of legitimate general concern, with respect to large and more primary issues of religious conviction - is pure reactionary evil. Up-tight, Victorian, 'fundamentalist', 'fascist'...
For modernity, sex comes before any-and-all religion - sex trumps religion; religion (to be ethical) must fit-itself-around sexual priorities. By law, enforced by govt. regulations, enforced by employers, enforced by mainstream mass media...
But wait a minute! At the same time, sex and sexuality are at the very centre of modern socio-political strategies - all major institutions and organisation in the modern state now incorporate sexual priorities among their declared 'mission statements' - none are exempt. No evaluation is exempt. No adverse functional consequences negate this priority: not sickness, death, annihilation... Whether it is the police or military, government or law, health services or education... all modern institutions and corporations must structure themselves around dogmas of sexuality and sexual identity.
So where does that leave us? As always, and from its surface to its fundamental depths; Leftism is incoherent. And since the sexual revolution is the battering ram, the shock troops of post-sixties New Leftism - the sexual revolution is incoherent. It does not make sense.
How come? Simple - because the sexual revolution is destructive in its essence - and destruction does not need to make sense. Indeed, sense is exactly-that which the sexual revolution, Leftism and (in the background) atheism seeks to destroy.
So far, its doing a great job!
This is why-and-how the sexual revolution is evil; because it is destructive. And it is purely destructive, destructive in its essence; which means that it is destructive of all Good.
Granted that the sexual revolution has destroyed some evils, along with the very concept of Good; it is necessary for people to recognise that this is the very nature of evil; the reason for its appeal and the way that evil corrupts.
In reality, Leftism is nowadays, mainly, the sexual revolution; and the sexual revolution is the incoherent enforcement of a whim of iron - simultaneously and incoherently whim-sical and of iron-necessity; hence destructive, hence - eventually - destructive of every-thing: everything Good, and bad, and indifferent.
Until, eventually, there is such chaos of mutually-resentful short-termist selfishness, that nothing can be done about anything.
And that situation is what's called hell.