I think the operative word is "easier".
A good number of modern graphics cards (pretty much any Radeon) do the true arcade resolutions, but require a utility like PowerStrip. There is a very good
write-up in this section about how to go about it.
The Multi-mode monitors make the PowerStrip approach even easier than the fixed 15khz models, as they are able to sync to standard PC resolutions until the true arcade res is required (IE. boot screens, non-interlaced desktops, etc.)
In short, your choice will depend on how much effort you want to put into it, but you don't
need a non-standard card to get true arcade resolutions.
RandyT