<p><strong>Let's look at the data.</strong>  First up is a plot of acceptance rates <em>versus</em> the number of answers, with a weighted GAM smooth superimposed (courtesy <code>ggplot2</code>).  It shows $11,609$ users.</p>

<p><a href="https://i.stack.imgur.com/jQFto.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jQFto.png" alt="Figure 1"></a></p>

<p>The strongest signal is a strong "learning effect" for those with $25$ or fewer answers.  (There are many possible explanations: it's not necessarily due to learning to write high-quality answers, but could be a matter of self selection.)</p>

<p>(The data are from a query at <a href="https://data.stackexchange.com/stats/query/edit/623920#resultSets" rel="nofollow noreferrer">https://data.stackexchange.com/stats/query/edit/623920#resultSets</a>.)</p>

<p>Next is a Pareto curve showing Total reputation <em>versus</em> rank for the top 2000 users. </p>

<p><a href="https://i.stack.imgur.com/hdvcu.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/hdvcu.png" alt="Figure 2"></a></p>

<p>The points show a strikingly linear relationship for ranks 51 - 2000 (the blue line is a linear fit to those points), but is sublinear for ranks 1-50.  The top five reputations are only one-third to one-tenth what would be predicted by the extrapolated line.</p>

<p>(The data are from  <a href="https://data.stackexchange.com/stats/query/578093/elite-users-those-who-hold-x-of-all-reputation#resultSets" rel="nofollow noreferrer">https://data.stackexchange.com/stats/query/578093/elite-users-those-who-hold-x-of-all-reputation#resultSets</a>.)</p>

<p>Finally, look at reputation per post.  I have limited this to people with at least 10 posts: 1725 users in all.</p>

<p><a href="https://i.stack.imgur.com/wIJHH.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/wIJHH.png" alt="Figure 3"></a></p>

<p>A correct interpretation would require incorporating the amount of time each post has been viewable on the site: posts, especially upvoted ones, tend to continue accumulating votes (growing by 10-20% per year).</p>

<p>(These data were obtained from <a href="http://data.stackexchange.com/stats/query/106236/users-with-highest-reputation-per-post" rel="nofollow noreferrer">http://data.stackexchange.com/stats/query/106236/users-with-highest-reputation-per-post</a>.)</p>

<hr>

<p>I will let you ponder these plots (and hope you might make some for yourself), so I will refrain from much commentary.  Let me just summarize.</p>

<p>Any adequate analysis would have to take time into account.  However, these raw data can be explained well by supposing that people who are good at solving statistical problems and communicating those solutions well have tended to be active on this site and that their high reputations partially reflect those skills.</p>

<p>Because plenty of the most active users (say, those with more than 100 answers) have relatively low acceptance rates and reputation per post, there is plenty of evidence that a "rich get richer" phenomenon, if it exists at all, explains only a small part of the reputation and is not universal.</p>
