My guess is that Microsoft’s own resources have to go into supporting enterprise commitments to M365 Copilot (and other Copilots) and their Azure OpenAI service. Bing Chat is easier to carve out from the enterprise / Azure stack.
I'd say Google is in trouble, I mean there is a limit to how many ads you can pack on the first page of results and I'd say they've passed it a long time ago.
In that context Bing + GPT would be more of a winner I think.
That's why most implementations add a layer of Retrieval-augmented generation (RAG): https://docs.aws.amazon.com/sagemaker/latest/dg/jumpstart-fo...