That's now how the auto
That's now how the auto industry works.
When you want to introduce something, you do it at the highest level so high-paying customers are getting something for their money. The Ascent let's them put in digital rear view mirror, 5k towing, etc that get introduced to lower vehicles (Outback then Forester, etc) and this is pretty standard.
I think what you're going for is just naming, because they are all built on the Subaru Global Platform, have similar 4 cylinder engines, 8.7" clearance, AWD, etc., so in a way the Ascent is the bigger Outback which is the bigger CrossTrek.