This plot depicts the birth years of people with Wikipedia articles and thus gives a sense of the distribution of notable people throughout history. Even when adjusted for live births per year (yielding the percentage of newborns in each year who will go on to be notable), the modern era clearly dominates.
The notable fraction of the world population might really be increasing, but the effect is compounded by the selection bias of our communal memory (helped along by the poor survival rate of records). The bar for notability or even remembrance is simply much lower for recent history.
More subtlety, normalizing by live births isn't quite fair, as infant and child mortality rates were much higher in the past and many of those births never had a chance to be notable. Unfortunately, it's difficult to estimate historic infant mortality (estimating birthrate is hard enough), so this normalization will have to do. (This effect can be crudely estimated as a factor of two or three at most - not nearly large enough to account for the data.)
Interestingly, from the steep downturn after the mid-1980s, we can also estimate the average age at first notability as roughly 30.
This dataset was collected from the May 2, 2014 archive of Wikipedia. 994,987 articles were tagged by birth year categories. 976,197 were tagged by precise years, while 12,054 were tagged by decade, 6,687 by century, and 45 by millennium. When exact birth year was not tagged, the individual was prorated over the appropriate time period.