Just an update on my dealer visit this past weekend. They didn't do any adjusting but they did add some really thick lub stuff that I will refer to as Satan snot and it seems to have helped. It has closed with no effort so far. They did tell me that if I was still having trouble to call them back and they would have their "world class" Subaru mechanic who doesn't work on Saturdays look at it.
Hmmm I'm having a similar issue on our new 2021. I need to SLAM the rear hatch closed in order for it to truly close.
The night we drove it home, I was behind my wife in our other Subie. and spotted that the little Subie lights in the side mirrors were on. She pulled over and the hatch was ajar. We slammed it shut and came home. When we got home we noticed that if you just closed the hatch it will not latch all the way. You need to slam it shut. We thought this might be due to the rear cargo protector being new and stiff...nope. I was thinking I'm going to need to take this in. Then I looked at the weather stripping and now I'm thinking maybe they forgot to cut this correctly.
When you open the hatch there is a LOUD sort of a popping sound. louder than I am used to anyway on the Ascent and the xB.