He's not wrong in this case, it's doable. There are many startups building similar services with arguably fewer starting resources. You should run completely in the other direction, but it's not impossible.
Credit products, especially virtual, are easier to create than ever thanks to companies that have built out that infrastructure. Chequing can be facilitated and held by a major bank under the hood in most cases.
It might not be his end game, but it's definitely possible. Now, forgive me while I weep for anyone that uses it if they manage to deliver it.
