Modern databases on modern server hardware are not limited by disk bandwidth typically, though Postgres is not a modern design and struggles to use the disk ban

Modern databases on modern server hardware are not limited by disk bandwidth typically, though Postgres is not a modern design and struggles to use the disk bandwidth available. That said, since these queries are accessing roughly the same data, concurrent queries will mostly be hitting cache. Memory bandwidth is often a larger limitation for databases these days, so it would still be wasteful.