You are forgetting many people use Excel on the Web nowadays, running on the same WebAssembly infrastructure as well.
And Microsoft would rather push everyone to the 365 Web subscription, than keeping selling native Excel, which by the way, nowadays uses plenty of React Native code instead of pure C++, exactly because of code portability to Office 365.
And Microsoft would rather push everyone to the 365 Web subscription, than keeping selling native Excel, which by the way, nowadays uses plenty of React Native code instead of pure C++, exactly because of code portability to Office 365.