[cogman10]

And, to be clear, those benefits are the placement of new records in a DB.

If a UUID is completely random it means it can be inserted anywhere which can require the DB to reshuffle records and pages in order to make room for the new record.

Having a sequential element to the UUID makes it a lot easier to have an index where each record is inserted at the end. Which, like you said, makes page usage more efficient and decreases the amount of work a DB has to do on insertion.

All this is a compounded problem if you have a DB with frequent writes, a lot of indexes, or both.