If you look at many people's reddit/usenet/facebook comment history, 23 entries per day isn't much
Sad to see SE contributors are compared with FB users.
While the occasional comment feels like work (e.g. citations), that isn't the norm so 23/day is meaningless.
Plus SO answers actually contribute positively to the world, whereas arguably social media comments do not.
[ example meant to highlight the difference between a low-impact, low-effort comment from a social media site like reddit versus sites like SO where some degree of technical expertise is a precondition ]
Also, if you are passionate about a topic, replying answers comes very naturally to you.
But I don't expect HN to get it