Azure is subsidized by Microsoft so they retain customers and mindshare, they also seem to have a mix of talent working for them. In some areas like reporting dashboards and such, Azure is head and shoulders better than AWS and GCP, but few if any of their large clients use these features (missing the primary value you'd get from using Azure).

Our interaction with the GCP sales team has repeatedly been aggressive US based sales agents, whereas Microsoft sent us to deal with (incompetent) sales agents out of India after promising us significant startup credits when we crossed paths with them at a conference near Seattle.

I think the regular prices for cloud services are super high. a1.xlarge has 4 vcpus and 8GB memory for $500 a year? They can afford to give a lot for free.