Regarding 1, there would need to be 2% more ideas every year than the year before in order to maintain growth of 2% annually. Regarding point number 2, since ideas are non-rival, there should be a greater diversity of creative perspectives.
The capital accessible to each worker remains constant when investment per worker equals depreciation per worker.
Regarding claim 1, the majority of individuals enjoy greater levels of living. Once inflation is taken into account, many resource prices in regard to 2 simply decreased. (If you want to learn more about this, look at, for instance, D E Sullivan, J L Sznopek, and L A Wagner's article, 20th century US mineral prices drop in constant dollars, published by the USGS and available online.)
The y=Ak models contend that larger saving ratios will result in sustained higher growth rates, in contrast to the neoclassical growth model.
If a nation's gross domestic product (GDP), which measures its output of goods and services, remains constant and a higher portion is exported, then a lesser portion is available to help its own population.
The argument that "the poor country may have a higher saving ratio" is insufficient to explain why a poor country might fall behind a rich country. A nation with a high saving and investment ratio will have a higher production per worker than a nation with a lower ratio, all else being equal.
The economy will end up with more capital per worker and higher living standards if people save and invest a higher percentage of their incomes while everything else remains the same. However, it would require some other factor, particularly sustained technological growth, to secure further sustained increases in living standards.
