Time sortable UUIDs can be useful when you have many different data sources you aggregate into one table and these data sources all need to assign IDs to the ev

Time sortable UUIDs can be useful when you have many different data sources you aggregate into one table and these data sources all need to assign IDs to the events. By having a 128-bit ID with timestmap upper and random lower bits the risk for collisions is low and by having the first bits be a time stamp you ensure that inserts are quite often done in sequential order, which is good for btrees. There are other solutions for this problem, and I do not think I would pick UUIDs or ULIDs myself, but it is a decent solution for this specific problem and does not waste much space compared to the other solutions.