Even when using as much stat samples as possible (3000000) for each of those tables: ALTER TABLE table_name ALTER column_name SET STATISTICS 10000; See https://www.postgresql.org/docs/current/sql-altertable.html

AFAIK the PostgreSQL's approach is based upon http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.53....