Since you have an LE its probably manual hatch so my guess would be for power hatch.
Thanks @kolkh! I'm hoping to find out if these are used by a feature intended for higher trims but that could be added to the LE relatively easily through the use of these connectors. We shall see!@Crafter4250 ,
If you are concerned about your specific Sienna LE, don't be! By coincidence I was working on my LE today and opened up the cover of the tailgate. I observed the same two unused connectors. See photo below: View attachment 62698