They have been releasing similar gains/performance for years now... Pretty much never has one company been dominant for a long time (except the initial GPT3/4 release I suppose. That period took a while for others to catch up)
I expect they will continue optimizing and improving for the current use cases/benchmarks. But the core capabilities will stagnant, that's why they will be forced to slow down until another major breakthrough happens.
I personally don't think LLMs have any understanding of the world, nor any imagination or even agency. I think it got very good as recognizing patterns and shapes in human thinking, language and knowledge, but that's pretty much it.