Developers are always going to risk going out of business, it wont matter if the 2nd hand market is stopped.
At the end of the day, if a game is obviously shit, it wont sell regardless if its 1st or 2nd hand.
The easiest way to avoid going out of business, make better bloody games
Obviously you must know this is a simplification. Good games aren't guaranteed sales in the slightest. Rehashed IPs and licensed games are, however.
What this potentially does is give more profit for the developer, allowing more risk taking. It doesn't guarantee it of course. But current climate almost demands those rehashes in favor of anything else