Why would GameStop have gone bust? Even if GameStop stock would trade at zero, the company still exists until it runs out of money and declares bankruptcy, which is independent of its stock price.

In this case, it's not really saving any jobs, since GameStop employees (excluding higher ranked employees) probably don't have any part of their compensation that's stock based.

Toys R Us was a leveraged buyout, which is definitely a much more ethically dubious strategy, and that can cause jobs to be lost. This won't cause any jobs at GameStop to be lost, although there probably will be some unhappy traders and people left holding bags of GameStop stock.