Horror story of the year
That may be a story of a year in the 2000s. Indeed, on that mailing list, the last messages actually relating to the project were sent in January 2012. Replying to somebody asking if "anything happened since [the quoted email] was posted in 2009", Sjors Gielen wrote:
Shortly after that e-mail, I concluded that running Debian within Cygwin is not possible, as it was impossible to update the system while it was running.
https://lists.debian.org/debian-win32/2012/01/msg00000.html
Was it a horror story though? I believe it is good to bring free software to Windows users.
It would be like making a frankenstein out of windows though. Not in a bad way, but it would be more profitable altogether just to make a debian fork that is libre altogether.
Gnuinos is supposedly one such attempt.