That is more of an engineering problem than a physics problem.
You need to keep in mind that just because something is possible does not mean that it will be adopted. There are many external factors that dictate whether some "invention" is successful or not. For example, we can build very strong buildings that can withstand the strongest earthquakes, but if it costs way more than anyone can afford, then no one is going to pursue that. The invention of anything requires not just a device that can do something, but also other factors such as costs, the feasibility of mass production, etc... etc. If your levitating car costs way more money to operate than the typical vehicle, how many people do you think will adopt it?
These are all not physics issues. And invention that do not consider any of those other factors are often doomed to disappear into obscurity.
Zz.