In the American culture (and many others, but more noticeably in the American) there is an association with the ability to drive a private vehicle (mostly being a car or a motorcycle) and the feeling of freedom. In the U.S. this can be very true, but it is precisely because of the lack of public transportation available in the country with only a few exceptions (being the very large cities such as New York and Chicago where public transportation is necessary because of the density of the city). However, with a well developed public transportation system it is quite the opposite.
In the U.S. the city layout is designed for commodity (while in countries where there is a longer history cities grew organically and chaotically), and therefore tend to be divided into residential areas and business areas (while in other countries they are mixed). Apartments are also lacking in the U.S. and are often frowned upon by many (even though it is the most efficient form of housing to conserve surface area). This means that there is now a larger distance between you and the closest grocery store in the U.S. due to the fact that it is in another neighborhood and the lack of density from compact residency structures. Because of these long distances and lack of public transportation the only way to get from point A to point B is to take a form of private transportation, therefore its connection to freedom. Many adolescents rely on their parents to get from one place to another until they are 16 and can get their driver’s license. However, this is not to say that public transportation would not provide the same freedom, or even more.
In countries such as Spain where there is a decent public transportation system available people of all ages have the ability to move quickly to any location in the city (and many towns) for a small price and without having to worry about insurance, gas prices, or parking. This means that youths (who cannot drive because they are not old enough) and the elderly (who cannot drive because of many debilitations that happen as one ages) can use the public transportation and be independent instead of dependent, and although it is true that you would be dependent on the state, the reliance on the state would be much more stable and much more affordable. People who cannot afford a car can still get to their job without taking out a loan for a new car that they might not be able to pay off. This also means that people have to walk/bike from the stops to their destination which helps in multiple aspects: health (the more they walk the less obesity), business (when people walk they are calmer and more willing to stop by any business they see that they find interesting), and psychological health (people would meet each other on the streets and be able to socialize, something that is good for us psychologically).
If taken with the right mindset, public transportation can also relieve stress. When one takes their car somewhere they need to pay attention to the road causing a bit of stress, but not only that, but if you need to be somewhere on time you feel relieved that you have no control over what time you get somewhere on public transportation, and if you get there late it is not your fault. This stress reliever is very useful in a society where people are constantly stressed to have a pause/break between activities to stop and reflect, read a book, listen to music, anything as long as you are calm doing it.
However, creating this sort of infrastructure is expensive, and even more so in a country with a city structure such as that of the U.S. which are more spread out. However, it must also be noted that the U.S. also has a lot more money than most countries, and can afford such a form of public transportation. So the more public transportation you have the more freedom you will have. Yet it must also be said that countries such as the U.S. will have no choice but to move towards public transportation because of population density. As population grows so will density and the need for public transportation (since not everyone in a large city can drive a car, it would cause too much traffic), and there will be no choice but to implement more and more public transportation and little by little getting rid of the private vehicles.