As mentioned, it’s not difficult to have a profitable business when staff is incredibly lean and the company’s landed a pilot project with their first client. But, this doesn’t really translate or provide any indicators of long-term success. The amount of growth that a company will have to undergo before it becomes a mature, sustainable company is monumental. Achieving profitability on $15k of revenue doesn’t give me any indication of where they’ll be when they’re mature. It certainly doesn’t hurt, but similarly, it doesn’t prove anything.
Product designers don’t strictly do UX — understanding the flow from screen to screen and the experience from onboarding to daily use. They also don’t strictly do UI — manipulating pixels and color in an icon, or adjusting the padding and typeface in a header. They use skills in both places to make the product as a whole better.