“A tallit gadol can be any color.” IMHO, possibly, but up to a certain point. It is possible to say (I would have to check) that color Eino MeAkev. But an argument of Lo Titgodedu could be made if one’s Tallit is sufficiently different from the rest of a Tzibbur’s (e.g., multicolored striped Tallit in the presence of white/white and black/white Tallaitim), such that it stands out.
Another thought concerning black stripes (vs. white stripes) is that they resemble the Retzuot of Tefillin (which are black, halacha LeMoshe MiSinai), thereby elevating somewhat the degree or seriousness of one’s Tallit, especially during Tefilla.