The hurdle for OpenAI is going to be on the profit side. Google has their own hardware acceleration and their own data centers. OpenAI has to pay a monopolist for hardware acceleration and beholden to another tech giant for data centers. Never mind that Google can customize it's hardware specifically for it's models.

The only way for OpenAI to really get ahead on solid ground is to discover some sort of absolute game changer (new architecture, new algorithm) and manage to keep it bottled away.