[pgaddict]

I'm not quite sure why you consider this "user error"? I work on the optimizer a bit, and I wouldn't say it's a fault of the user ...

OTOH I'm not sure it's a fault of the DB either :-( The statistics collected by ANALYZE are pretty much a lossy compressed version of the database, and so some details are missing - that's kinda the point of collecting the stats.

I'm not sure why lowering the autoanalyze threshold would fix this - it increases the frequency of stats updates, so my feeling is it makes it more likely to trigger similar issue. OTOH increasing the statistics target seems like the right thing to do (although it also keeps more accurate stats, not just increase the sample size).

I don't know if there are better solutions (both practical and in principle) :-(