ReactNative for Windows uses WinUI and XAML Islands, which is UWP, aka COM.

I really don't know what kind of COM you have been writing, because COM from VCL, MFC, ATL, UWP, Delphi, .NET surely doesn't fulfill that description.

As for what COM is good for,

"Component Software: Beyond Object-Oriented Programming"

https://www.amazon.com/Component-Software-Object-Oriented-Pr...