Also, the original Lucasfilm Commodore 64 games, such as Maniac Mansion, were cross-compiled on UNIX workstations, transferred over the network and uploaded to running C64s — way back in 1987! (Source: The Thimbleweed Park podcasts [0], which I highly recommend.)
Three years earlier, the development for the 1984 game "Match Point" for ZX Spectrum (the graphics in the video is original, the sound is fake by the youtube video producer):
https://www.youtube.com/watch?v=eRO_nY-d94w&t=22s
was done by then-just-software company named Psion on their VAX computer:
https://archive.org/stream/sinclair-user-magazine-036/Sincla...
And for developing on the early Macintosh you had to have a Lisa Workstation[1]
[1] http://www.folklore.org/StoryView.py?story=3rd_Party_Develop...
https://en.wikipedia.org/wiki/Altair_BASIC
Paul Allen wrote an emulator for the microprocessor which run on PDP-10. He was able to extend his previous version of emulator for that.
At the time Microsoft developed MS-DOS (actually modifying the program they have bought), around 1981, they owned their own DECSYSTEM-2060:
https://en.wikipedia.org/wiki/DECSYSTEM-20