Good point. I actually forgot that Jeep had a parent company. They did a great job distinguishing themselves.Look at it from the consumer's point of view: Does someone go to a Dodge/Chrysler/Jeep/RAM dealer, or do they search out a Jeep dealer, regardless of whatever else may be around?
There may be other cars at a dealer store, but someone shopping for a Jeep is only looking for a Jeep dealer. Same with RAM -- if you're shopping pickups, you're looking for a RAM, no mater what purple or lime sedans are around.
One of the benefits of Jeep's "independent" sub-branding is there's virtually zero brand recognition of Chrysler as the source of Jeep by the vast majority of the public. Put another way, the Jeep brand is virtually immune to any Chrysler foibles, and they benefit accordingly.
Not sure why Ford's doing it with Bronco, but FCA has isolated the brands with the only significant value in the entire FCA group. They are ideally positioned for sale as individual entities if needed in the future. When Chrysler purchased the remnants of American Motors, they had to take along all the rest of the worthless AMC stuff to get the Jeep brand.