[becurious]

The message map macros were the equivalent of the switch statement in a WndProc. They couldn’t add every Windows message as a virtual override because every derived class would have needed thousands of vtable entries. At the time memory was still very limited (4MB systems for Windows 95 and they also had support for 16 bit Windows where it would have been even worse).

Also the template support in the compiler was limited at the time. Later on there were other libraries that used templates like ATL and WTL.

You did get a lot for free from MFC when implementing document editing applications for OLE support, but that was an increasingly small portion of development.

I think Borland went a different way with compiler extensions for producing a Win32 application with their OWL library.