Embedded stuff usually, game consoles. Also if you have an Enterprise SKU of Visual Studio it costs real money to upgrade. Maybe your company has purchased a compiler suite you have to use. Maybe you have to link against proprietary libs that were only provided for a certain MSVC ABI.
Exactly, that's why one would get excited for C++ support.
However, I realise the point is moot since there would be no way to compile the library. I've been living too long in "Compiles to C" languages this month I guess.