This is almost a word-for-word description of the dev workflow for a proprietary embedded OS I worked on as an intern. Even the "simulator" was what you describ

This is almost a word-for-word description of the dev workflow for a proprietary embedded OS I worked on as an intern. Even the "simulator" was what you describe - some #ifdefs that turn the program into a cli program using Win32. This worked for us because our approach was to "make it right the first time, update only when necessary."