Some more data from the For You perspective.
This graph uses the date of the first and the last visit of the For You feed users. This is a bit different from Patrick's analysis.
How about this - you create a For You "peek" link which other people can use to temporarily turn their For You into your For You.
They get to see how you curated your feed.
Would you want to set who can peek? Options: everyone, followers, mutuals.
I wouldn't draw too many conclusions from the analysis of For You users vs all Bluesky users because of the huge selection bias.
But it is probably safe to assume that helping people discover good feeds is generally good for user retention.