Most people are in a situation where they're forced to use a car every day. This situation could be resolved through smarter planning, better urban design, and alternative methods of transportation.
Two hundred years ago nobody needed a car because it didn't exist. Now people need it because parts of society are so entangled with it that it's nearly impossible to pull them apart.
If somehow planes had wrangled their way into our lifestyle the same way, then yes, people would need a plane every day. How else would they get home to their chalet in an inaccessible part the woods six hundred miles from the office at the end of a work-day?
I don't want to argue pointlessly, but while your conclusion may be right, I think your logic makes some leaps. Why is day the natural time scale? No one needs a plane every hour and no one needs a car every hour either. By that time scale, they are the same. Also, everyone needs a plane every year and needs a car every year too. On that time scale they are also the same. Only in a cherry-picked intermediate time scale are they different. :) I think your answer would be improved if you could justify why the daily time scale is most relevant.
The time scale in fact can go the other direction and still favor cars. It's about cost per use.
If you drive every day like many Americans, it's cheaper to own a car than to use a cab. The number of people that fly enough to need their own plane is effectively zero.
No they aren't. Many people need a car every day. Almost nobody needs a plane every day.