Whatever.
I don’t know if it’s ok to nurse in public or not, But,
It is much less tzius than most of the things you people rant about on this site.
To wit, it is less tznius than:
Skirts with a slit,
wearing red,
leggings,
bare calves,
open toe,
jean skirts,
etc.
So I am not going to criticize it, but if you won’t wear a slit skirt (slit below knee), then you probably shouldn’t be nursing in public.