Are there? OpenAI is currently the only provider. Big tech companies (Google, MS, Meta, maybe Apple) may also soon have similar models but they don't have much incentive to sell access to them. Smaller orgs can't produce GPT-level AI. It feels like all these products are really at the mercy of OpenAI.
There has been an explosion of effort around LLama, but Meta did the hard part (the base model), and who knows if they will do that again.
This is one of many, many open LLM models that are approaching GPT level now. They're not on the same level yet, but given the rate of progress in this field, it's safe to say that OpenAI's moat will not be there forever.
Also, their level is already sufficient for A LOT of tasks that people use OpenAI's APIs now.