3 of those are about Exchange and one is about Bing (involving AAD, but it was an AAD app that was misconfigured and not an AAD issue itself). The teams that run Azure are in entirely separate organizations with wildly different product stacks.
Exchange has a bunch of decades old infrastructure and is a security nightmare afaik. Dunno much about Bing.
The "org chart" graphic with MS orgs all pointing guns at each other is real shit. Different orgs have very different security postures, and Azure's is much stronger than others.
Source: spent some time at MS