Jennifer: ^ But sometimes games have 16-bit installers for other programs (for example I was unable to install Beyond Good & Evil from my disc because of the damned DRM and had to buy the game again on GOG), or require a really old version of Quicktime (like the original Myst), or something like that where it doesn't work or takes a lot of jumping through hoops to make it work.
That's true, I would actually amend my claim to say that when Windows 95 was out, that should have been the end for 16-bit programs, since there was absolutely no need or benefit to write them - not for the developer nor the user.
However, for all sorts of reasons, there were still 16-bit programs being made for the 32-bit OS for some time. Many times installers and things that were supposed to be backwards compatible with Windows 3.1 and such.
But I guess my point was that any commercial program today is either 32-bit or 64-bit, so for maximum compatibility today, 64-bit Windows is always the more compatible one to today's applications. Legacy support and old programs or drivers are something else and never come into play when a new game is released.