It’s a missed opportunity in my opinion, “here’s an accurate Win2K/XP/7 replica desktop that you get to keep forever” is a strong pitch for Linux for a lot of potential users.
It has massive nostalgia appeal but is also practical because it signals to users that they won’t need to learn any new UI bits or behaviors and that they’ll be comfortable right away. It removes a lot of the spookiness of switching that comes with even the most Windows-like DEs like KDE.
For win9x/win2k style this is really neat: