In defense of the modern iteration of the Disney Princess, she exhibits positive qualities well-suited to Disney’s target primary school age audience . The Princess(es) is/are often orphan(s) or otherwise separated from their parents (e.g. Rapunzel in Tangled), but this separation serves a narrative purpose. Removal from parental oversight causes the Disney Princess to be/become self-reliant and proactive. These are important qualities for primary kids to see and value as they learn to take small steps away from their own parents.
The Disney Princess is not grasping or materialistic, in the way a slur like "she’s such a princess" might suggest. She works hard, even if born into privilege. She is compassionate and kind. She explores or goes off on adventures and overcomes barriers. She has a positive, can-do attitude. She stands up to evil and wrong-doing even at personal cost. She wins the day by being a good person and doing what is morally right, even when that's not the easy choice.
To focus on a lack of career ambition or to worry about a weak match-making sub-plot is to read too much into characters that are mainly proxies for primary grade girls. Close observation of primary girls watching these films tells me that such threads are accepted as the macguffins they are, but otherwise ignored. Prince-chasing never seems to factor into subsequent role-play.
Having the kids see and want to emulate these strong, kind, and capable female characters is not a bad thing at all. It's a lack of such role models as they outgrow the animated Disney offerings that should perhaps concern us more.