Shader model aside...would you get decent framerates on SM2 generation hardware? That's, what, GF6xxx and Radeon 8xxx series, no?
Actually, it was perfectly viable at the time. It was only the lack of SM2.0 support that prevented the game from running. Not only that but it didn't warn you, it simply produced a black screen. I had to upgrade my graphics card to run the game, as I had an X800XL at the time.