Is it possible to tell when databases, schemas and tables were created in Postgres?
From this post:

;WITH CTE AS
(
    SELECT 
        table_name 

        ,
        (
            SELECT 
                MAX(pg_ls_dir::int)::text 
            FROM pg_ls_dir('./base') 
            WHERE pg_ls_dir &lt;&gt; 'pgsql_tmp' 
            AND  pg_ls_dir::int  &lt;= (SELECT relfilenode FROM pg_class WHERE relname ILIKE table_name)
        ) as folder 


        ,(SELECT relfilenode FROM pg_class WHERE relname ILIKE table_name) filenode

    FROM information_schema.tables
    WHERE table_type = 'BASE TABLE'
    AND table_schema = 'public'
)

SELECT 
    table_name 
    ,(
        SELECT creation 
        FROM pg_stat_file(
            './base/' || folder || '/' || filenode 
        )
    ) as creation_time
FROM CTE;


But, from the comment to this post here, this method is sometimes unreliable. Use at your own risk! You might also be interested in this - it appears that PostgreSQL is finally going down the road of an Oracle wait interface.

If you'd care to file a feature request and post the link in a comment here (with @Vérace in the body), I'd be happy to file a "me-too".