Random UUID's are super useful when you have distributed creation of UUID's, because you avoid conflicts with very high probability and don't rely on your DB to generate them for you, and they also leak no information about when or where the UUID was created.
Postgres is happier with sequence ID's, but keeping Postgres happy isn't the only design goal. It does well enough for all practical purposes if you need randomness.
Postgres is happier with sequence ID's, but keeping Postgres happy isn't the only design goal. It does well enough for all practical purposes if you need randomness.