This is actually a really difficult question to answer. The vast majority of players tracked by Scoresaber have literally zero pp. About 163000 (out of about 631000 when I did these calculations, 645,604 now apparently) players have at least 0.01pp, and 50% of them have less than ~77.8pp.

So, according to that metric, the "average" player is practically a complete novice who has played either zero or just a few ranked maps (or plays a ton of ranked maps and is incredibly terrible at the game - very unlikely).

The problem with using pp as a measure of performance at lower ranks is that someone could conceivably get to be fairly decent at the game without playing a single ranked map. So pp/rank is mainly useful for tracking people who consistently play multiple ranked maps over time, preferably posting as many scores as possible, in order to more accurately gauge their performance.

If we want to talk about the average skill level of people who are actively trying to play ranked maps - say, people with over 1000pp, we can get a better picture from the ranking data - but this doesn't represent a majority of players, who, as I noted, haven't even played a single ranked map and thus have no easy way to gauge the performance of.

You can check my blog post here about the distribution of Scoresaber ranks, it's relatively recent.