Is there any point in getting "primogeniture" early in CK3?

Restoring charolingian empire or forming archduchy of austria gives primogeniture very early. But I can manage succession easily by murdering unwanted sons near death or being sure to have 1 son and a second one as backup plan that i can disinherit. Managing extra heirs fees too much easy compared with how much hard is to get primogeniture immediately.