@Rory Cooper - Thanks for the question and using MS Q&A platform.
I agree that it looks like an error message but it's a warning message to indicates:This account may not have enough CPU cores to satisfy this request
Note: This is not the error message and it's just a warning message.
I had tried to create a cluster with single node which consumes 4 cores and able to successfully create the cluster without any issue.
Even this is not the error message and it's just a warning message.
I agree that it looks like an error message but it's a warning message to indicates that the : This account may not have enough CPU cores to start the cluster. Contact your administrator to increase the limits.
If the issue persists, try in another region.
Refer to this similar thread: Unable to create cluster in Azure Databricks because I don't have enough cpu cores to create cluster But I didn't use my vcpus in my region
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