The problem with $50,000 tickets is a higher price means fewer customers, and at a certain point that means less money coming in overall, worse economies of scale, and less ability to cover your upfront engineering costs.
The Toyota Camry is a $30,000 car that sells 300,000 units per year. The Lamborghini Huracan is a $300,000 car that sells 600 units per year. Much easier to cover the costs of developing a reliable electrical system, or a new hybrid drivetrain, when you're Toyota.
Concorde couldn't repay its development costs for the same reason.
In fairness, there's little practical benefit (and, in fact, a lot of downsides) to a supercar whereas a plane that does trans-oceanic in half the time is useful--of course, if you can build it, and sell tickets economically for maybe today's business class prices--keeping in mind that a lot of people flying business are doing so on upgrades/miles.
I used to work for a big 6 accountancy and audit firm. their senior partners used to fly concorde, wheras us underlings flew virgin upper class (like first class on other carriers).
Government people. I remember Kissinger flying on it.
A first class ticket on the Titanic would be $50,000 today.