I think gojo needs to hold his hand in front of his face to expand his domain, and if so, Saitama could dodge it until gojo runs out of cursed energy. He doesn't have infinite, even if the six eyes give him a great deal of efficiency, he is shown to be visibly exhausted after expanding his domain in Shibuya, although that could be because he killed over a thousand transfigured humans in 0.2 seconds