Bruh, they are asking for a well put together app with all the features you'd have in production. From an intern. You are right in that a senior dev could bang this out, but it would still take them a day at least. Interns generally don't know what they are doing. If they did they would be going for the higher paid job already. How does asking for an entire MVP from an intern ever make sense?

Even if they paid him to make this app it would stop being unethical but it would still be silly.