Apple has enforced this same restriction on numerous app developers and companies before. The only reason for this being "bigger news" is the pre-existing rivalry between Apple and Microsoft, or more likely because of Microsoft's PR team.
It's also something that most people don't agree with, so every time it happens, it gets a lot of discussion. Maybe eventually Apple will have some solution that doesn't involve getting 30% for doing nothing.
Apple has enforced this same restriction on numerous app developers and companies before. The only reason for this being "bigger news" is the pre-existing rivalry between Apple and Microsoft, or more likely because of Microsoft's PR team.