Also, providing and consuming a basic COM interface is quite easy with Miscrosoft's development tools. This is not true in other ecosystems.
So COM did not fail as a standard, it just failed to conquer the whole world. It's doing fine though in its natural habitat.
I have a different experience writing and using COM with C++. I remember ugliness around reference counting, dealing with the literally dozen of methods of defining a string and having to coerce them into BSTRs and having to deal with variant types that were a weird C union type.
I remember going to a class at Embedded Systems Conference that showed how to implement a COM interface in assembly on a microcontroller. Was cool, but I had no use for that, although we were using COM/DCOM at the higher levels.
That sounds cool, though. Seeing protocols/formats/algorithms laid bare in assembly code makes them comprehensible in a way that I don't get from high level language implementations, where I have to either be content in just hand-waving away understand any "sugar" the language itself implements, or also having to understand the language's contrivances on top of whatever the core thing is I'm trying to understand.