Never doubt GS. Its been only nine months since GS entered its newly created consumer lending venture, and the platform has been a successful so far. With over $1bn loan already and room to grow, borrowers have been attracted to Marcus's user-friendly experience, lower rates than credit cards, no late fees, fast turnaround times, and great human customer service.
As far as growth potential, Goldman's balance sheet gives it the ability to grow Marcus as quickly (or slowly) as it wants. And with approximately $1 trillion of unsecured debt in the U.S., there is a huge addressable market.
https://www.fool.com/investing/2017/07/24/how-goldman-sachs-is-disrupting-this-1-trillion-in.aspx