If a man wants to get the most out of life, a proper understanding of the meaning of life is very important. If a man is religiously misguided, then it doesn’t matter whether he is capable of competing. He won't achieve it anyway.
In this respect, one has to differentiate between different religions. Christianity, for example, is more of an obstacle than Islam. The more pious one is in Christianity, the more restricted one’s sexual options become. For some really pious Catholics, an idealized path is the priesthood, which means that all sex is forbidden.
Islam is, in fact, sexually more permissive than Christianity. One should not judge sexual permissiveness merely by comparing how apologetic a society is regarding typical modern US boyfriend/girlfriend relationships.
While in the Christian afterlife, humans are generally considered to transcend earthly sexuality, the opposite is traditionally depicted in the Islamic paradise. Not only are Muslim martyrs promised a paradise with plenty of young, willing companions, but they are also promised virgins who have never been with other men and whom they do not have to share.
Even the most pious men in Islam are not only allowed to have sex, families, and offspring, but they may also have multiple wives if they desire and can fulfill the necessary conditions. Throughout history, Muslim religious and worldly leaders often had their harems. Popes, by contrast, had to do their philandering in secrecy.
If one were forced to live in the Middle Ages, equipped with enough intelligence to achieve wealth and a secure social position, I would pray to be placed in the Muslim, rather than the Christian, world.
Even nowadays, and under certain circumstances, Muslim societies may be a better option than Christian ones (if simply for the fact that they are more immune to US cultural exports).
Outside the Old World (Europe) and the New World (the Americas), there is still the Third World, which, on the one hand, is characterized by poverty, corruption, and megacities, and on the other hand, by archaic, fantasy-inspired alternatives to the modern world, as these could only blossom in the third millennium in an under-policed environment.