The main point about so-called substitutes for religion that are not actual religions, that that They Don't Work. That is, secular 'substitutes' for religion are not really substitutes; because they do not perform the same function.
After Christianity began to decline in The West, in the early 1800s, the first ideological substitutes included pacifism, abolition (i.e. of slavery), nationalism and socialism. Nowadays, when there are very few self-identified Christians (and even fewer real Christians) it is often said that ideologies such as feminism, antiracism, sexual subversion and revolution, and environmentalism (i.e. the spectrum of post-sixties New Left-ism) have become substitute religions; imposing increasingly elaborate and extensive rituals, and requiring frequent pious affirmations and ejaculations.
But although there are superficial similarities, modern ideologies are not genuine substitutes for religion because they are materialist and this-worldly; which means that their bottom line is merely the temporary and contingent state of human psychological gratification.
Because modern ideologies exclude God, gods, the spiritual world, the soul, existence beyond biological death and all the rest of it; ideologies do not provide any deep or lasting basis for human motivation.
Aside from family love; religion was the single most powerful long-term motivator of Men. The ability of religion to motivate powerfully was based upon its 'supernatural' aspects; and when these were discarded, so was the power to motivate.
Some of the secular ideologies in the first generation after real-religion was abandoned did retain a residual power to motivate; especially among those who were brought-up religiously. Strong motivation was (in effect) carried-over from the childhood religious environment.
For example the first generation of Soviet Communists included some highly motivated (and therefore self-sacrificing) individuals, with a religious level of devotion to the cause. But this rapidly faded as genuine atheism and materialism took a grip, and the later USSR suffered profound - indeed fatal - nihilism and despair.
The immediately post-Christian Nationalists were also sometimes highly motivated, to the level of great courage and personal self-sacrifice. But the example of German National Socialism shows that this seemed also to require a strongly mystical and supernaturalist quality. In other words, an element of real religion.
In sum; at a personal level, then, there is no ideological substitute for real religion. Confirmation is that the absence of a real religion is invariably associated with significant sub-fertility (i.e. average fertility rate significantly less than two children per woman).
Self-chosen extinction is the ultimate evidence for grossly deficient motivation at the population level.
In a social sense, the Mass Media has become the main substitute religion, in terms of being the centre of general social attention.
For all known historical societies; 'religion' (broadly defined, but always 'supernaturalist') was the primary agent of social cohesion. These were the beliefs and practices that united societies. Nowadays, the nearest equivalent are the Mass (and social) Media; that provide the common subject matter and perspectives of conversations and policies.
So, the Mass Media construct and shape reality for modern societies in a broadly similar way that religions used to.Are they then the new religion?
No, because there is a fundamental and decisive difference; which is that religions are cohesive, while the modern Mass Media are fissile. Modern Mass Media are negative, not positive; they are against, not for.
Of course the Mass Media are chaotic, multi-perspectival and self-contradicting at the micro-level; but overall and in the long-term they are organised by hostility to The Good and to God; by their subversion, destruction and inversion of all that was held true, beautiful and virtuous; by their erosion of all taboos and exclusions.
In other words, (real) religions hold things together; while the Media breaks things apart.
So there is no substitute for religion; but only partial and superficially-similar analogies to religion. Some aspects of real religion can be substituted by secular alternatives, but not all; and not the most important.
The socially-visible defect of the modern ideologies and Media is that they fail to provide motivation and fail to provide positive grounds for cohesion. Thus we get societies of demotivated and isolated, increasingly mutually-hostile, individuals.
It is therefore misleading to talk about substitutes for religion. The stark fact is that there is no substitute for religion, and it is lack of religion - specifically Christianity - that is the prime cause of our condition.
If ever we want The West to become motivated and positively purposeful, and to sustain itself rather than committing slow-suicide; there must first be religion.