In adults, there's also the excessive indulgence in caffeinated drinks like coffee, and energy drinks which masks sleep deprivation.
That's because the Anglo-American world mostly has a tradition of a large evening meal (instead of a large midday meal) and is largely not in a warm climate; siesta, by varying names, is most common where warm climate and large midday meals coincide, and even there have often been displaced in the modern workforce though long lunch breaks often remain in an echo of the tradition.
Even if the first part was true (it's not), the second part is unlikely to be the explanation: Protestantism, even the Calvinism most associated with the “Protestant work ethic”, isn't a unique feature of the Anglosphere.