Every few months we get another post like this, with a slightly different measure. Yes, lots of Azure workloads run Linux, and Microsoft makes it a priority. It's not news anymore.
At the same time, Azure itself runs largely on Windows servers in Service Fabric (https://github.com/Microsoft/service-fabric), so it's hard to count. With nested hypervisors as the normal architecture nowadays, this whole tally is pretty suspect.
But we (the tech community) never seem to get bored with the "Microsoft is eating humble pie on OSS" story. Maybe that's exactly what Microsoft deserves after so many years of big-bad-wolf behavior. Unfortunately it makes their real engineering and OSS feats hard for us to see or acknowledge.
Like Service fabric. Did you know that Microsoft built and open sourced an orchestrator that can manage tens if millions of nodes with totally diverse workloads (containers, VMs, and bare metal), nested hypervisors, and even nested orchestrators in a secure multi tenant context? That beats the crap out of kubernetes on a capabilities front, but it's not an easy story to sell. Or that Windows Hyper-V has done thin-VM/M container isolation on par with kata and firecracker for years? Or that many (if not most) Azure services are open source? You can run the entire azure stack on your home server closet if you like, especially including their biggest growth areas of kubernetes and ML/cognitive services. If you want an open source alternative to AWS, azure can be a real option.
I enjoy the historical irony of this as much as the next guy, but we really have to stop letting it blind us to the awesome things MS is doing that don't fit that narrative. Microsoft is benefiting mightily by adopting open source culture, code, and practices as fast as it can. And if we can get our heads out of our own self-righteous asses enough to upvote the stories, we can profit from it too.