That's how people view how wealthy and successful a person is, through material possessions. Owning a house, a car, and being able to travel the world. I understand your point OP, that wealth doesn't really come from material things. And if you happen to accept that you're wealthy, it's actually how you view the world. If you economically think that not owning a car is fine, then that's fine. You don't need any validation from these people who happen to pay mortgage and car payments, which makes them cringe when the due date is near. At the end of the day, it's how you live your life. If you happen to enjoy it with or without those things, as long as you're not drowning in debt, I guess that's one of the definitions of the real financial freedom and success.
Financial wealth is mostly gaining misconceptions. Some just see it as merely buying house and lot, cars and different assets, and they find theirselves already wealthy and successful, even if they know they are drown in debt. However for me, the real wealthy and successful are those who stay silent behind their achievements and success in life. No need for validations, because we don’t live for others but we live for our own selves.
Don’t let others define you. If you know you are wealthy and successful on your own, then continue doing it and moving forward. Focus on positive and constructive motivations, do not dwell on people who have opposite views from yours.