Optimized for Microsoft, not for the user.
Optimized for Microsoft, not for the user. That's about the sum of it.
They got it right in 1995 when they aped the RISC OS taskbar. They didn't need to change it after that.
But they did ... to force the user to see what *they* wanted the user to see. Internet Explorer, Bing Search, Cortana (which is really Clippy), Copilot (which is really Cortana), OneDrive, more OneDrive, ads, ads, ads, ads, and more OneDrive.
They got it right, once, and have been ruining it ever since.