If you talked about the average read time, then on average, longer stories will accommodate more read time compare to the shorter stories. Getting curated is one of the best things could happen with you on Medium including getting published in a popular publication.
I published a story comparing my ration of reading time/member read time, a story that got far fewer views but was 10 minutes get more read time compared to a story that got more views but less reading the time.
You can read the complete story here.
Is Lengthy Medium Stories Make More Money?
A comparison of two stories with a length of 6 — Minutes Read Time Verses 3 — Minutes Read Time
I hope this will helps.