Anyway, maybe that small bump is one of the starting ratings, and maybe there's the typical chess.com nonsense of some small error causing inactive players to appear on the graph. (It's supposed to be only "active" players.)
Ohh true I hadn't thought about the starting ratings. I'm sure there's a big group of people that started at 800, lost their first game, went to like 770, then never played again.
Could it be counting people who have never played any rated games at all? They open their account, get a starting-rating of 800, and then only do puzzles or play unrated games against bots? Just speculating.
For what I know, the graphs includes only players who played at lesat one game in the previous 90 days.
The odd bump could be caused by new users showing up with all the same "rating", like "new to chess" at 400, or other choices, getting one 600 or 800. As it looks like many make the choice that'll grant them a 800 Elo for first rating (which is then no rating at all until some games are actually played).
Can anyone think of why this weird bump exists in the rating distribution of chess.com players? It seems to be right around the average rating so I'm just curious of any theories behind the cause of this. This is the distribution for all blitz players but it seems to be there for rapid and bullet as well though it isn't quite as pronounced.